title:
Two RPG Flow-graphs for Software Watermarking using Bitonic Sequences of
  Self-inverting Permutations

abstract:
  Software watermarking has received considerable attention and was adopted by
the software development community as a technique to prevent or discourage
software piracy and copyright infringement. A wide range of software
watermarking techniques has been proposed among which the graph-based methods
that encode watermarks as graph structures. Following up on our recently
proposed methods for encoding watermark numbers $w$ as reducible permutation
flow-graphs $F[\pi^*]$ through the use of self-inverting permutations $\pi^*$,
in this paper, we extend the types of flow-graphs available for software
watermarking by proposing two different reducible permutation flow-graphs
$F_1[\pi^*]$ and $F_2[\pi^*]$ incorporating important properties which are
derived from the bitonic subsequences composing the self-inverting permutation
$\pi^*$. We show that a self-inverting permutation $\pi^*$ can be efficiently
encoded into either $F_1[\pi^*]$ or $F_2[\pi^*]$ and also efficiently decoded
from theses graph structures. The proposed flow-graphs $F_1[\pi^*]$ and
$F_2[\pi^*]$ enrich the repository of graphs which can encode the same
watermark number $w$ and, thus, enable us to embed multiple copies of the same
watermark $w$ into an application program $P$. Moreover, the enrichment of that
repository with new flow-graphs increases our ability to select a graph
structure more similar to the structure of a given application program $P$
thereby enhancing the resilience of our codec system to attacks.


title:
On the Complexity and Approximability of Budget-Constrained Minimum Cost
  Flows

abstract:
  We investigate the complexity and approximability of the budget-constrained
minimum cost flow problem, which is an extension of the traditional minimum
cost flow problem by a second kind of costs associated with each edge, whose
total value in a feasible flow is constrained by a given budget B. This problem
can, e.g., be seen as the application of the {\epsilon}-constraint method to
the bicriteria minimum cost flow problem. We show that we can solve the problem
exactly in weakly polynomial time $O(\log M \cdot MCF(m,n,C,U))$, where C, U,
and M are upper bounds on the largest absolute cost, largest capacity, and
largest absolute value of any number occuring in the input, respectively, and
MCF(m,n,C,U) denotes the complexity of finding a traditional minimum cost flow.
Moreover, we present two fully polynomial-time approximation schemes for the
problem on general graphs and one with an improved running-time for the problem
on acyclic graphs.


title:
Adaptive seamless design for establishing pharmacokinetics and efficacy
  equivalence in developing biosimilars

abstract:
  Recently, numerous pharmaceutical sponsors have expressed a great deal of
interest in the development of biosimilars, which requires clinical trials to
demonstrate the equivalence of pharmacokinetics (PK) and clinical efficacy.
Pharmacodynamics (PD) may be used in evaluating efficacy if there are relevant
PD markers available. However, in their absence, it is necessary to design the
associated clinical trials to include efficacy measures as the primary
endpoint. In this study, we propose an adaptive seamless PK and efficacy design
with the frameworks to remedy the risk of misspecification of both PK and
efficacy parameters. Here, we consider the clinical development of biosimilars
including their evaluation in patients rather than healthy volunteers under a
situation where both PK and efficacy parameters are required to demonstrate the
equivalence. To avoid the risk associated with the failure to confirm
equivalence, incorporating the new PK trial for PK equivalence within the PK
portion, which is the early stage for the efficacy part, and sample size
re-calculation for the efficacy equivalence are considered in the proposed
method. This proposal provides appealing advantages such as a shorter period,
additional cost saving, and smaller number of patients required.


title:
A Network Simplex Method for the Budget-Constrained Minimum Cost Flow
  Problem

abstract:
  We present a specialized network simplex algorithm for the budget-constrained
minimum cost flow problem, which is an extension of the traditional minimum
cost flow problem by a second kind of costs associated with each edge, whose
total value in a feasible flow is constrained by a given budget B. We present a
fully combinatorial description of the algorithm that is based on a novel
incorporation of two kinds of integral node potentials and three kinds of
reduced costs. We prove optimality criteria and combine two methods that are
commonly used to avoid cycling in traditional network simplex algorithms into
new techniques that are applicable to our problem. With these techniques and
our definition of the reduced costs, we are able to prove a pseudo-polynomial
running time of the overall procedure, which can be further improved by
incorporating Dantzig's pivoting rule. Moreover, we present computational
results that compare our procedure with Gurobi.


title: Removable Singularities of $m$-Hessian Equations

abstract:
  In this paper we give a new, less restrictive condition for removability of
singular sets, $E$, of smooth solutions to the m-Hessian equation (and also for
more general fully nonlinear elliptic equations) in $\Omega \setminus E$,
$\Omega \subset \mathbb R^n$. Besides the existence and regularity results for
these equations, the proof only makes use of the classical elliptic theory,
i.e. the classical maximum principles and a Hopf lemma.


title: The boundness of weighted Coxeter groups of rank 3

abstract:
  We prove that a weighted Coxeter group (W,S,L) is bounded in the sense of
G.Lusztig if the rank of W is 3.


title:
Symmetry Enriched U(1) Topological Orders for Dipole-Octupole Doublets
  on a Pyrochlore Lattice

abstract:
  Symmetry plays a fundamental role in our understanding of both conventional
symmetry breaking phases and the more exotic quantum and topological phases of
matter. We explore the experimental signatures of symmetry enriched U(1)
quantum spin liquids (QSLs) on the pyrochlore lattice. We point out that the Ce
local moment of the newly discovered pyrochlore QSL candidate
Ce$_2$Sn$_2$O$_7$, is a dipole-octupole doublet. The generic model for these
unusual doublets supports two distinct symmetry enriched U(1) QSL ground states
in the corresponding quantum spin ice regimes. These two U(1) QSLs are dubbed
dipolar U(1) QSL and octupolar U(1) QSL. While the dipolar U(1) QSL has been
discussed in many contexts, the octupolar U(1) QSL is rather unique. Based on
the symmetry properties of the dipole-octupole doublets, we predict the
peculiar physical properties of the octupolar U(1) QSL, elucidating the unique
spectroscopic properties in the externalmagnetic fields. We further predict the
Anderson-Higgs transition from the octupolar U(1) QSL driven by the external
magnetic fields. We identify the experimental relevance with the candidate
material Ce$_2$Sn$_2$O$_7$ and other dipole-octupole doublet systems.


title:
Colloids Exposed to Random Potential Energy Landscapes: from Particle
  Number Density to Particle-Potential and Particle-Particle Interactions

abstract:
  Colloidal particles were exposed to a random potential energy landscape
(rPEL) that has been created optically via a speckle pattern. The mean particle
density as well as the potential roughness, i.e. the disorder strength, were
varied. The local probability density of the particles as well as its main
characteristics were determined. For the first time, the disorder-averaged pair
density correlation function and an analogue of the Edwards-Anderson order
parameter, which quantifies the correlation of the mean local density among
disorder realisations, were measured experimentally and shown to be consistent
with replica liquid state theory results.


title:
An ergodic BSDE approach to forward entropic risk measures:
  representation and large-maturity behavior

abstract:
  Using elements from the theory of ergodic backward stochastic differential
equations (BSDE), we study the behavior of forward entropic risk measures. We
provide their general representation results (via both BSDE and convex duality)
and examine their behavior for risk positions of long maturities. We show that
forward entropic risk measures converge to some constant exponentially fast. We
also compare them with their classical counterparts and derive a parity result.


title: Non-Central Catadioptric Cameras Pose Estimation using 3D Lines

abstract:
  In this article we purpose a novel method for planar pose estimation of
mobile robots. This method is based on an analytic solution (which we derived)
for the projection of 3D straight lines, onto the mirror of Non-Central
Catadioptric Cameras (NCCS). The resulting solution is rewritten as a function
of the rotation and translation parameters, which is then used as an error
function for a set of mirror points. Those should be the result of the
projection of a set of points incident with the respective 3D lines. The
camera's pose is given by minimizing the error function, with the associated
constraints. The method is validated by experiments both with synthetic and
real data. The latter was collected from a mobile robot equipped with a NCCS.


title:
A Survey of Cellular Automata: Types, Dynamics, Non-uniformity and
  Applications

abstract:
  Cellular automata (CAs) are dynamical systems which exhibit complex global
behavior from simple local interaction and computation. Since the inception of
cellular automaton (CA) by von Neumann in 1950s, it has attracted the attention
of several researchers over various backgrounds and fields for modelling
different physical, natural as well as real-life phenomena. Classically, CAs
are uniform. However, non-uniformity has also been introduced in update
pattern, lattice structure, neighborhood dependency and local rule. In this
survey, we tour to the various types of CAs introduced till date, the different
characterization tools, the global behaviors of CAs, like universality,
reversibility, dynamics etc. Special attention is given to non-uniformity in
CAs and especially to non-uniform elementary CAs, which have been very useful
in solving several real-life problems.


title: Depth-controlled Bessel beams

abstract:
  We present a ring aperture with independently switchable segments for the
three-dimensional control of quasi propagation invariant beams. We demonstrate
that our liquid crystal design concept preserves coherence and generates the
Bessel beam structure.


title:
Experimental creation and characterization of random potential energy
  landscapes exploiting speckle patterns

abstract:
  The concept of potential energy landscapes is applied in many areas of
science. We experimentally realize a random potential energy landscape (rPEL)
to which colloids are exposed. This is achieved exploiting the interaction of
matter with light. The optical set-up is based on a special diffuser, which
creates a top-hat beam containing a speckle pattern. This is imposed on
colloids. The effect of the speckle pattern on the colloids can be described by
a rPEL. The speckle pattern as well as the rPEL are quantitatively
characterized. The distributions of both, intensity and potential energy
values, can be approximated by Gamma distributions. They can be tuned from
exponential to approximately Gaussian with variable standard deviation, which
determines the contrast of the speckles and the roughness of the rPEL.
Moreover, the characteristic length scales, e.g. the speckle size, can be
controlled. By rotating the diffuser, furthermore, a flat potential can be
created and hence only radiation pressure exerted on the particles.


title: Average coherence and its typicality for random mixed quantum states

abstract:
  Wishart ensemble is a useful and important random matrix model used in
diverse fields. By realizing induced random mixed quantum states as Wishart
ensemble with the fixed-trace one, using matrix integral technique we give a
fast track to the average coherence for random mixed quantum states induced via
partial-tracing of the Haar-distributed bipartite pure states. As a direct
consequence of this result, we get a compact formula of the average subentropy
of random mixed states. These obtained compact formulae extend our previous
work.


title:
Semiclassical ground-state phase diagram and multi-Q phase of a
  spin-orbit coupled model on triangular lattice

abstract:
  Motivated by recent experiments on the frustrated quantum magnetic compound
YbMgGaO4, we study an effective spin model on triangular lattice taking into
account the effects of the spin-orbit coupling. We determine the classical
ground-state phase diagram of this model, which includes a 120 degree Neel and
two collinear antiferromagnetic phases. In the vicinity of the phase boundary
between the Neel and collinear phases, we identify three intermediate
non-collinear antiferromagnetic phases. In each of them the magnetic moments
are ordered at multiple incommensurate wave vector Q values. We further study
the effects of quantum fluctuations in this model via a linear spin-wave
theory. We find that the spin excitation gap of the non-collinear multi-Q
antiferromagnetic state is finite but can be vanishingly small, and this state
is unstable to a spin liquid phase under strong quantum fluctuations in some
large J_{z+-} regime.


title:
On the evolution of cooperation under social pressure in multiplex
  networks

abstract:
  In this work, we aim to contribute to the understanding of the human
pro-social behavior by studying the influence that a particular form of social
pressure "being watched" has on the evolution of cooperative behavior. We study
how cooperation emerge in multiplex complex topologies by analyzing a
particular bidirectionally-coupled dynamics on top of a two-layers multiplex
network (duplex). The coupled dynamics appears between the Prisoner's Dilemma
game in a network, and a threshold cascade model in the other. The threshold
model is intended to abstract the behavior of a network of vigilant nodes, that
impose pressure of being observed altering hence the temptation to defect of
the dilemma. Cooperation or defection in the game also affects the state of a
node of being vigilant. We analyze these processes on different duplex networks
structures and assess the influence of the topology, average degree and
correlated multiplexity, on the outcome of cooperation. Interestingly, we find
that the social pressure of vigilance may impact cooperation positively or
negatively, depending on the duplex structure, specifically the degree
correlations between layers is determinant. Our results give further
quantitative insights in the promotion of cooperation under social pressure.


title: Modulated nematic structures and chiral symmetry breaking in 2D

abstract:
  We have studied the properties of biaxial particles interacting via an
anisotropic pair potential, involving second rank quadrupolar and third rank
octupolar coupling terms, using Monte Carlo simulation. The particles occupy
the sites of a 2D square lattice and the interactions are restricted to nearest
neighbours. The system exhibits spontaneous chiral symmetry breaking from an
isotropic phase to a chiral modulated nematic phase, composed of ambidextrous
chiral domains. When two-fold axes of quadrupolar and octupolar tensors
coincide this modulated phase appears to be the ambidextrous cholesteric phase
of pitch comparable with a few lattice spacings, which can be regarded as a
limiting case of the nematic twist bend phase. The associated phase transition
is first-order.


title: On Channel Resolvability in Presence of Feedback

abstract:
  We study the problem of generating an approximately i.i.d. string at the
output of a discrete memoryless channel using a limited amount of randomness at
its input in presence of causal noiseless feedback. Feedback does not decrease
the channel resolution, the minimum entropy rate required to achieve an
accurate approximation of an i.i.d. output string. However, we show that, at
least over a binary symmetric channel, a significantly larger resolvability
exponent (the exponential decay rate of the divergence between the output
distribution and product measure), compared to the best known achievable
resolvability exponent in a system without feedback, is possible. We show that
by employing a variable-length resolvability scheme and using an average number
of coin-flips per channel use, the average divergence between the distribution
of the output sequence and product measure decays exponentially fast in the
average length of output sequence with an exponent equal to $[R-I(U;V)]^+$
where $I(U;V)$ is the mutual information developed across the channel.


title:
Condition-based maintenance at both scheduled and unscheduled
  opportunities

abstract:
  Motivated by original equipment manufacturer (OEM) service and maintenance
practices we consider a single component subject to replacements at failure
instances and two types of preventive maintenance opportunities: scheduled,
which occur due to periodic system reviews of the equipment, and unscheduled,
which occur due to failures of other components in the system. Modelling the
state of the component appropriately and incorporating a realistic cost
structure for corrective maintenance as well as condition-based maintenance
(CBM), we derive the optimal CBM policy. In particular, we show that the
optimal long-run average cost policy for the model at hand is a control-limit
policy, where the control limit depends on the time until the next scheduled
opportunity. Furthermore, we explicitly calculate the long-run average cost for
any given control-limit time dependent policy and compare various policies
numerically.


title:
Towards controlling the dissociation probability by light-induced
  conical intersections

abstract:
  Light-induced conical intersections (LICIs) can be formed both by standing or
by running laser waves. The position of a LICI is determined by the laser
frequency while the laser intensity controls the strength of the nonadiabatic
coupling. Recently, it was shown within the LICI framework that linearly
chirped laser pulses have an impact on the dissociation dynamics of the
$D_{2}^{+}$ molecule (J. Chem. Phys. 143, 014305, (2015); ibid 144, 074309,
(2016)). In this work we exploit this finding and perform calculations using
chirped laser pulses in which the time dependence of the laser frequency is
designed so as to force the LICI to move together with the field-free
vibrational wave packet as much as possible. Since nonadiabaticity is strongest
in the vicinity of the conical intersection, this is the first step towards
controlling the dissociation process via the LICI. Our showcase example is
again the $D_{2}^{+}$ molecular ion. To demonstrate the impact of the LICIs on
the dynamical properties of diatomics, the total dissociation probabilities and
the population of the different vibrational levels after the dissociation
process are studied and discussed.


title:
Hong-Ou-Mandel interference between two independent all fiber photon
  sources

abstract:
  Guided-wave platforms such as fiber and silicon-on-insulator waveguide show
great advances over traditional free space implementations in quantum
information technology for significant advantages of low transmission loss, low
cost, integrability and compatible with mature fiber communication systems.
Interference between independent photon sources is the key to realize complex
quantum systems for more sophisticated applications such as multi-photon
entanglement generation and quantum teleportation. In this work, we report
Hong-Ou-Mandel interference between two independent all fiber photon pair
sources over two 100GHz dense wave division multiplexing channels, the
visibility reaches 53.2(8.4)% (82.9(5.3)%) without (with) back ground counts
subtracted. In addition, we give a general theoretical description of the
purity of the photon pair generation in dispersion shifted fiber and obtain the
optimized condition for high purity photon pair generation. We also obtain a
maximum coincidence to back ground ratio of 131 by cooling the fiber in liquid
nitrogen. Our study shows great promising of integrated optical elements for
future scalable quantum information promising.


title: Mott lobes of the $S=1$ Bose-Hubbard model with three-body interactions

abstract:
  Using the density matrix renormalization group method, we studied the ground
state of the one-dimensional $S=1$ Bose-Hubbard model with local three-body
interactions, which can be a superfluid or a Mott insulator state. We drew the
phase diagram of this model for both ferromagnetic and antiferromagnetic
interaction. Regardless of the sign of the spin-dependent coupling, we obtained
that the Mott lobes area decreases as the spin-dependent strength increases,
which means that the even-odd asymmetry of the two-body antiferromagnetic chain
is absent for local three-body interactions. For antiferromagnetic coupling, we
found that the density drives first-order superfluid-Mott insulator transitions
for even and odd lobes. Ferromagnetic Mott insulator and superfluid states were
obtained with a ferromagnetic coupling, and a tendency to a "long-range" order
was observed.


title:
CNN-LTE: a Class of 1-X Pooling Convolutional Neural Networks on Label
  Tree Embeddings for Audio Scene Recognition

abstract:
  We describe in this report our audio scene recognition system submitted to
the DCASE 2016 challenge. Firstly, given the label set of the scenes, a label
tree is automatically constructed. This category taxonomy is then used in the
feature extraction step in which an audio scene instance is represented by a
label tree embedding image. Different convolutional neural networks, which are
tailored for the task at hand, are finally learned on top of the image features
for scene recognition. Our system reaches an overall recognition accuracy of
81.2% and 83.3% and outperforms the DCASE 2016 baseline with absolute
improvements of 8.7% and 6.1% on the development and test data, respectively.


title:
Free-free and H42alpha emission from the dusty starburst within NGC 4945
  as observed by ALMA

abstract:
  We present observations of the 85.69 GHz continuum emission and H42alpha line
emission from the central 30 arcsec within NGC 4945. Both sources of emission
originate from nearly identical structures that can be modelled as exponential
discs with a scale length of ~2.1 arcsec (or ~40 pc). An analysis of the
spectral energy distribution based on combining these data with archival data
imply that 84% +/- 10% of the 85.69 GHz continuum emission originates from
free-free emission. The electron temperature is 5400 +/- 600 K, which is
comparable to what has been measured near the centre of the Milky Way Galaxy.
The star formation rate (SFR) based on the H42alpha and 85.69 GHz free-free
emission (and using a distance of 3.8 Mpc) is 4.35 +/- 0.25 M/yr. This is
consistent with the SFR from the total infrared flux and with previous
measurements based on recombination line emission, and it is within a factor of
~2 of SFRs derived from radio data. The Spitzer Space Telescope 24 micron data
and Wide-field Infrared Survey Explorer 22 micron data yield SFRs ~10x lower
than the ALMA measurements, most likely because the mid-infrared data are
strongly affected by dust attenuation equivalent to A_V=150. These results
indicate that SFRs based on mid-infrared emission may be highly inaccurate for
dusty, compact circumnuclear starbursts.


title:
Field-Enhanced Kondo Correlations in a Half-Filling Nanotube Dot:
  Evolution of an SU(N) Fermi-Liquid Fixed Point

abstract:
  We theoretically study an emergent SU(2) symmetry which is suggested by
recent magneto-transport measurements, carried out near two electrons filling
of a carbon nanotube quantum dot. It emerges in the case where the spin and
orbital Zeeman splittings cancel each other out for two of the one-particle dot
levels among four. Using the Wilson numerical renormalization group, we show
that a crossover from the SU(4) to SU(2) Fermi-liquid behavior occurs at two
impurity-electrons filling as magnetic field increases. We also find that the
quasiparticles are significantly renormalized as the remaining two one-particle
levels move away from the Fermi level and are frozen at high magnetic fields.
In order to clarify how the ground state evolves during such a crossover, we
also reexamine the SU(N) Kondo singlet state for M impurity-electrons filling
in the limit of strong exchange interactions. We show that the nondegenerate
Fermi-liquid fixed point of Nozi\`{e}es and Blandin can be described as a
bosonic Perron-Frobenius vector for M hard-core bosons, each of which consists
of one impurity-electron and one conduction hole. This interpretation can also
be applied to the Fermi-liquid fixed-point without the SU(N) symmetry.


title:
CaR-FOREST: Joint Classification-Regression Decision Forests for
  Overlapping Audio Event Detection

abstract:
  This report describes our submissions to Task2 and Task3 of the DCASE 2016
challenge. The systems aim at dealing with the detection of overlapping audio
events in continuous streams, where the detectors are based on random decision
forests. The proposed forests are jointly trained for classification and
regression simultaneously. Initially, the training is classification-oriented
to encourage the trees to select discriminative features from overlapping
mixtures to separate positive audio segments from the negative ones. The
regression phase is then carried out to let the positive audio segments vote
for the event onsets and offsets, and therefore model the temporal structure of
audio events. One random decision forest is specifically trained for each event
category of interest. Experimental results on the development data show that
our systems significantly outperform the baseline on the Task2 evaluation while
they are inferior to the baseline in the Task3 evaluation.


title: Fibonacci Numbers, Statistical Convergence and Applications

abstract:
  The purpose of this paper is twofold. First, the definition of new
statistical convergence with Fibonacci sequence is given and some fundamental
properties of statistical convergence are examined. Second, approximation
theory worked as a application of the statistical convergence.


title: Uniqueness of density-to-potential mapping for fermionic lattice systems

abstract:
  We demonstrate that, for a fermionic lattice system, the ground-state
particle density uniquely determines the external potential except for the
sites corresponding to nodes of the wave function, and the limiting case where
the Pauli exclusion principle completely determines the occupation of all
sites. Our fundamental finding completes, for this general class of systems,
the one-to-one correspondence between ground states, their densities, and the
external potential at the base of the Hohenberg-Kohn theorem. Moreover we
demonstrate that the mapping from wave function to potential is unique not just
for the ground state, but also for excited states. To illustrate our findings,
we develop a practical inversion scheme to determine the external potential
from a given density. Our results hold for a general class of lattice models,
which includes the Hubbard model.


title:
Maximizing Hole Coherence in Ultrafast Photoionization of Argon with
  SPA-Optimization

abstract:
  Photoionization with attosecond pulses populates hole states in the photoion.
Superpositions of hole states represent ideal candidates for time-dependent
spectroscopy, for example via pump-probe studies. The challenge consists in
identifying pulses that create coherent superpositions of hole states while
satisfying practical constraints. Here, we employ quantum optimal control to
maximize the degree of coherence between these hole states. To this end, we
introduce a derivative-free optimization method with Sequential PArametrization
update (SPA-optimization). We demonstrate the versatility and computational
efficiency of SPA-optimization for photoionization in argon by maximizing the
coherence between the $3s$ and $3p_0$ hole states using shaped attosecond
pulses. We show that it is possible to maximize the hole coherence while
simultaneously prescribing the ratio of the final hole state populations.


title:
Collaborative Training of Tensors for Compositional Distributional
  Semantics

abstract:
  Type-based compositional distributional semantic models present an
interesting line of research into functional representations of linguistic
meaning. One of the drawbacks of such models, however, is the lack of training
data required to train each word-type combination. In this paper we address
this by introducing training methods that share parameters between similar
words. We show that these methods enable zero-shot learning for words that have
no training data at all, as well as enabling construction of high-quality
tensors from very few training examples per word.


title:
Second-order structured deformations: relaxation, integral
  representation and applications

abstract:
  Second-order structured deformations of continua provide an extension of the
multiscale geometry of first-order structured deformations by taking into
account the effects of submacroscopic bending and curving. We derive here an
integral representation for a relaxed energy functional in the setting of
second-order structured deformations. Our derivation covers inhomogeneous
initial energy densities (i.e., with explicit dependence on the position);
finally, we provide explicit formulas for bulk relaxed energies as well as
anticipated applications.


title: Magnon Polarons in the Spin Seebeck Effect

abstract:
  Sharp structures in magnetic field-dependent spin Seebeck effect (SSE)
voltages of Pt/Y$_{3}$Fe$_{5}$O$_{12}$ (YIG) at low temperatures are attributed
to the magnon-phonon interaction. Experimental results are well reproduced by a
Boltzmann theory that includes the magnetoelastic coupling (MEC). The SSE
anomalies coincide with magnetic fields tuned to the threshold of
magnon-polaron formation. The effect gives insight into the relative quality of
the lattice and magnetization dynamics.


title:
Effect of demagnetization factor dependence on energy of ultra-thin
  ferromagnetic films with four layers

abstract:
  Simple cubic and body centered cubic ferromagnetic lattices with four layers
were studied using Heisenberg Hamiltonian. According to 3-D plots, the films
with four layers can be easily oriented in certain directions under the
influence of particular demagnetization factor and angles for both sc(001) and
bcc(001) ferromagnetic lattice structures. A flat part can be seen in the
middle of 3-D plots in addition to periodic variations. When the
demagnetization factor is given by =6, sc(001) film with four layers can be
easily oriented in 0.6 radians direction for the energy parameter values used
in this simulation. Under the influence of demagnetization factor given by =5.2
, thin film of bcc(001) lattice with four layers can be easily oriented along
0.63 radians direction.


title:
Enhanced electron-phonon coupling in graphene with periodically
  distorted lattice

abstract:
  Electron-phonon coupling directly determines the stability of cooperative
order in solids, including superconductivity, charge and spin density waves.
Therefore, the ability to enhance or reduce electron-phonon coupling by optical
driving may open up new possibilities to steer materials' functionalities,
potentially at high speeds. Here we explore the response of bilayer graphene to
dynamical modulation of the lattice, achieved by driving optically-active
in-plane bond stretching vibrations with femtosecond mid-infrared pulses. The
driven state is studied by two different ultrafast spectroscopic techniques.
Firstly, TeraHertz time-domain spectroscopy reveals that the Drude scattering
rate decreases upon driving. Secondly, the relaxation rate of hot
quasi-particles, as measured by time- and angle-resolved photoemission
spectroscopy, increases. These two independent observations are quantitatively
consistent with one another and can be explained by a transient three-fold
enhancement of the electron-phonon coupling constant. The findings reported
here provide useful perspective for related experiments, which reported the
enhancement of superconductivity in alkali-doped fullerites when a similar
phonon mode was driven.


title: Axially symmetric static sources of gravitational field

abstract:
  A general procedure to find static and axially symmetric, interior solutions
to the Einstein equations is presented. All the so obtained solutions, verify
the energy conditions for a wide range of values of the parameters, and match
smoothly to some exterior solution of the Weyl family, thereby representing
globally regular models describing non spherical sources of gravitational
field. In the spherically symmetric limit, all our models converge to the well
known incompressible perfect fluid solution.The key stone of our approach is
based on an ansatz allowing to define the interior metric in terms of the
exterior metric functions evaluated at the boundary source. Some particular
sources are obtained, and the physical variables of the energy-momentum tensor
are calculated explicitly, as well as the geometry of the source in terms of
the relativistic multipole moments. The total mass of different configurations
is also calculated, it is shown to be equal to the monopole of the exterior
solution.


title:
Non - Topological Solitons in a Non-minimally Coupled Scalar Field
  Induced Gravity Theory

abstract:
  Properties of soliton stars that could be expected to naturally arise out of
a first order phase transition in non-minimally coupled scalar-field-induced
gravity theories are investigated. Of particular interest are configurations,
similar to Lee-Wick stars, with vanishing effective gravitational constant in
the interiors.


title:
Power-Availability-Aware Cell Association for Energy-Harvesting
  Small-Cell Base Stations

abstract:
  Energy harvesting brings a key solution to the increasing energy bill and
environmental concerns but, at the same time, the network availability may be
deteriorated due to potential energy shortage. In this paper, we analyze the
performance of off-grid small-cell base stations (scBS) with finite battery
capacity and design a new power-availability-aware cell association based on
periodical broadcast of the scBS battery level. Each mobile terminal (MT)
targets its own set of available scBSs before association, i.e. the set of
scBSs that can guarantee service provided (i) the scBS battery level, (ii) the
power required to satisfy a received power constraint at each MT, given the
scBS-MT distance and the shadowing attenuation, and (iii) the estimated power
consumed to serve other MTs potentially associated to the same scBS, which is
computed using stochastic geometry tools. Next, we develop for it a tractable
performance analysis and derive closed-form expressions for the probability of
power outage and the coverage probability. By dynamically adapting to the
fluctuations of the base station battery and user power requirement, the
proposed cell association allows a more even distribution of the available
energy in the network, brings robustness against harvesting impairment and
thereby, significantly outperforms conventional strategies.


title:
The Renewed Case for the Reduced Instruction Set Computer: Avoiding ISA
  Bloat with Macro-Op Fusion for RISC-V

abstract:
  This report makes the case that a well-designed Reduced Instruction Set
Computer (RISC) can match, and even exceed, the performance and code density of
existing commercial Complex Instruction Set Computers (CISC) while maintaining
the simplicity and cost-effectiveness that underpins the original RISC goals.
  We begin by comparing the dynamic instruction counts and dynamic instruction
bytes fetched for the popular proprietary ARMv7, ARMv8, IA-32, and x86-64
Instruction Set Architectures (ISAs) against the free and open RISC-V RV64G and
RV64GC ISAs when running the SPEC CINT2006 benchmark suite. RISC-V was designed
as a very small ISA to support a wide range of implementations, and has a less
mature compiler toolchain. However, we observe that on SPEC CINT2006 RV64G
executes on average 16% more instructions than x86-64, 3% more instructions
than IA-32, 9% more instructions than ARMv8, but 4% fewer instructions than
ARMv7.
  CISC x86 implementations break up complex instructions into smaller internal
RISC-like micro-ops, and the RV64G instruction count is within 2% of the x86-64
retired micro-op count. RV64GC, the compressed variant of RV64G, is the densest
ISA studied, fetching 8% fewer dynamic instruction bytes than x86-64. We
observed that much of the increased RISC-V instruction count is due to a small
set of common multi-instruction idioms.
  Exploiting this fact, the RV64G and RV64GC effective instruction count can be
reduced by 5.4% on average by leveraging macro-op fusion. Combining the
compressed RISC-V ISA extension with macro-op fusion provides both the densest
ISA and the fewest dynamic operations retired per program, reducing the
motivation to add more instructions to the ISA. This approach retains a single
simple ISA suitable for both low-end and high-end implementations, where
high-end implementations can boost performance through microarchitectural
techniques.


title:
Should the advanced measurement approach be replaced with the
  standardized measurement approach for operational risk?

abstract:
  Recently, Basel Committee for Banking Supervision proposed to replace all
approaches, including Advanced Measurement Approach (AMA), for operational risk
capital with a simple formula referred to as the Standardised Measurement
Approach (SMA). This paper discusses and studies the weaknesses and pitfalls of
SMA such as instability, risk insensitivity, super-additivity and the implicit
relationship between SMA capital model and systemic risk in the banking sector.
We also discuss the issues with closely related operational risk
Capital-at-Risk (OpCar) Basel Committee proposed model which is the precursor
to the SMA. In conclusion, we advocate to maintain the AMA internal model
framework and suggest as an alternative a number of standardization
recommendations that could be considered to unify internal modelling of
operational risk. The findings and views presented in this paper have been
discussed with and supported by many OpRisk practitioners and academics in
Australia, Europe, UK and USA, and recently at OpRisk Europe 2016 conference in
London.


title:
Wilson lines, Grassmannians and Gauge Invariant Off-shell Amplitudes in
  N=4 SYM

abstract:
  In this paper we consider tree-level gauge invariant off-shell amplitudes
(Wilson line form factors) in $\mathcal{N}=4$ SYM. For the off-shell amplitudes
with one leg off-shell we present a conjecture for their Grassmannian integral
representation in spinor helicity, twistor and momentum twistor
parameterizations. The presented conjecture is successfully checked against
BCFW results for MHV$_n$, NMHV$_4$ and NMHV$_5$ off-shell amplitudes. We have
also verified that our Grassmannian integral representation correctly
reproduces soft (on-shell) limit for the off-shell gluon momentum. It is shown
that the (deformed) off-shell amplitude expressions could be also obtained
using quantum inverse scattering method for auxiliary $gl(4|4)$ super spin
chain.


title:
Magnetic properties of Cobalt films described by second order perturbed
  Heisenberg Hamiltonian

abstract:
  Second order perturbed Heisenberg Hamiltonian was employed to investigate the
magnetic properties of hexagonal Cobalt films. Initially the number of nearest
neighbors and the constants arisen from the partial summation of the dipole
interactions of the structure of cobalt were calculated using some special
algorithms. Minimization of the energy difference between the easy and hard
direction of a memory device is very important. When the energy difference
between the easy and hard directions is significantly small, the magnetic
moments in a memory device can be quickly rotated between easy and hard
directions under the influence of a small magnetic field. The thickness of a
cobalt film corresponding to this minimum energy difference calculated using
this theoretical model agrees with some experimental data of cobalt based
magnetic memory devices.


title:
Particle dynamics in discs with turbulence generated by the vertical
  shear instability

abstract:
  Among the candidates for generating turbulence in accretion discs in
situations with low intrinsic ionization the vertical shear instability (VSI)
has become an interesting candidate, as it relies purely on a vertical gradient
in the angular velocity. Existing simulations have shown that $\alpha$-values a
few times $10^{-4}$ can be generated. The particle growth in the early planet
formation phase is determined by the dynamics of dust particles. Here, we
address in particular the efficiency of VSI-turbulence in concentrating
particles in order to generate overdensities and low collision velocities. We
perform 3D numerical hydrodynamical simulations of accretion discs around young
stars that include radiative transport and irradiation from the central star.
The motion of particles within a size range of a fraction of mm up to several m
is followed using standard drag formula. We confirm that under realistic
conditions the VSI is able to generate turbulence in full 3D protoplanetary
discs. The irradiated disc shows turbulence within 10 to 60au. The mean radial
motion of the gas is such that it is directed inward near the midplane and
outward in the surface layers. We find that large particles drift inward with
the expected speed, while small particles can experience phases of outward
drift. Additionally, the particles show bunching behaviour with overdensities
reaching 5 times the average value, which is strongest for dimensionless
stopping times around unity. Particles in a VSI-turbulent discs are
concentrated in large scale turbulent eddies and show low relative speeds that
allow for growing collisions. The reached overdensities will also allow for the
onset streaming instabilities further enhancing particle growth. The outward
drift for small particles at higher disk elevations allows for the transport of
processed high temperature material in the Solar System to larger distances.


title: Third Order Perturbed Energy of Cobalt Ferrite Thick Films

abstract:
  Magnetic properties and easy axis orientation of cobalt ferrite films with
applied magnetic field and number of layers were studied. According to our
theoretical studies explained in this manuscript, the magnetically easy and
hard directions of cobalt ferrite films solely depend on in plane and out of
plane magnetic fields. According to 3-D and 2-D plots, there are many easy and
hard directions at one particular value of in plane or out of plane magnetic
field. The magnetic properties were investigated for cobalt ferrite films with
thickness up to 10,000 unit cells. The total magnetic energy was calculated for
a unit spin of cobalt.


title: Neutron detectors for the ESS diffractometers

abstract:
  The ambitious instrument suite for the future European Spallation Source
whose civil construction started recently in Lund, Sweden, demands a set of
diverse and challenging requirements for the neutron detectors. For instance,
the unprecedented high flux expected on the samples to be investigated in
neutron diffraction or reflectometry experiments requires detectors that can
handle high counting rates, while the investigation of sub-millimeter protein
crystals will only be possible with large-area detectors that can achieve a
position resolution as low as 200 {\mu}m. This has motivated an extensive
research and development campaign to advance the state-of-the-art detector and
to find new technologies that can reach maturity by the time the ESS will
operate at full potential. This paper presents the key detector requirements
for three of the Time-of-Flight diffraction instrument concepts selected by the
Scientific Advisory Committee to advance into the phase of preliminary
engineering design. We discuss the available detector technologies suitable for
this particular instrument class and their major challenges. The detector
technologies selected by the instrument teams to collect the diffraction
patterns are briefly discussed. Analytical calculations, Monte-Carlo
simulations, and real experimental data are used to develop a generic method to
esti- mate the event rate in the diffraction detectors. The proposed approach
is based upon conservative assumptions that use information and input
parameters that reflect our current level of knowledge and understanding of the
ESS project. We apply this method to make predictions for the future
diffraction instruments, and thus provide additional information that can help
the instrument teams with the optimisation of the detector designs.


title: Optimal Bayesian estimators for latent variable cluster models

abstract:
  In cluster analysis interest lies in probabilistically capturing partitions
of individuals, items or observations into groups, such that those belonging to
the same group share similar attributes or relational profiles. Bayesian
posterior samples for the latent allocation variables can be effectively
obtained in a wide range of clustering models, including finite mixtures,
infinite mixtures, hidden Markov models and block models for networks. However,
due to the categorical nature of the clustering variables and the lack of
scalable algorithms, summary tools that can interpret such samples are not
available. We adopt a Bayesian decision theoretic approach to define an
optimality criterion for clusterings, and propose a fast and
context-independent greedy algorithm to find the best allocations. One
important facet of our approach is that the optimal number of groups is
automatically selected, thereby solving the clustering and the model-choice
problems at the same time. We consider several loss functions to compare
partitions, and show that our approach can accommodate a wide range of cases.
Finally, we illustrate our approach on a variety of real-data applications for
three different clustering models: Gaussian finite mixtures, stochastic block
models and latent block models for networks.


title: Particle methods for multi-group pedestrian flow

abstract:
  We consider a multi-group microscopic model for pedestrian flow describing
the behaviour of large groups. It is based on an interacting particle system
coupled to an eikonal equation. Hydrodynamic multi-group models are derived
from the underlying particle system as well as scalar multi-group models. The
eikonal equation is used to compute optimal paths for the pedestrians. Particle
methods are used to solve the equations on all levels of the hierarchy.
Numerical test cases are investigated and the models and, in particular, the
resulting evacuation times are compared for a wide range of different
parameters.


title:
Easy axis orientation of Strontium ferrite thin films described by spin
  reorientation

abstract:
  In plane orientation of magnetic easy axis of sputtered strontium hexaferrite
thin films has been explained using classical Heisenberg Hamiltonian. The
variation of average value of in plane spin component with temperature was
plotted in order to determine the temperature at which easy axis is oriented in
the plane of the strontium ferrite film. The average value of in plane spin
component in this 2-D model reaches zero at one particular temperature. This
particular temperature obtained using our theoretical model agrees with the
experimental value of the temperature of rf sputtered polycrystalline strontium
ferrite thin films deposited on polycrystalline Al2O3 substrates (500 0C). This
spin reorientation temperature solely depends on the values of energy
parameters used in our modified Heisenberg Hamiltonian equation.


title: Common and Distinct Components in Data Fusion

abstract:
  In many areas of science multiple sets of data are collected pertaining to
the same system. Examples are food products which are characterized by
different sets of variables, bio-processes which are on-line sampled with
different instruments, or biological systems of which different genomics
measurements are obtained. Data fusion is concerned with analyzing such sets of
data simultaneously to arrive at a global view of the system under study. One
of the upcoming areas of data fusion is exploring whether the data sets have
something in common or not. This gives insight into common and distinct
variation in each data set, thereby facilitating understanding the
relationships between the data sets. Unfortunately, research on methods to
distinguish common and distinct components is fragmented, both in terminology
as well as in methods: there is no common ground which hampers comparing
methods and understanding their relative merits. This paper provides a unifying
framework for this subfield of data fusion by using rigorous arguments from
linear algebra. The most frequently used methods for distinguishing common and
distinct components are explained in this framework and some practical examples
are given of these methods in the areas of (medical) biology and food science.


title:
Watch This: Scalable Cost-Function Learning for Path Planning in Urban
  Environments

abstract:
  In this work, we present an approach to learn cost maps for driving in
complex urban environments from a very large number of demonstrations of
driving behaviour by human experts. The learned cost maps are constructed
directly from raw sensor measurements, bypassing the effort of manually
designing cost maps as well as features. When deploying the learned cost maps,
the trajectories generated not only replicate human-like driving behaviour but
are also demonstrably robust against systematic errors in putative robot
configuration. To achieve this we deploy a Maximum Entropy based, non-linear
IRL framework which uses Fully Convolutional Neural Networks (FCNs) to
represent the cost model underlying expert driving behaviour. Using a deep,
parametric approach enables us to scale efficiently to large datasets and
complex behaviours by being run-time independent of dataset extent during
deployment. We demonstrate the scalability and the performance of the proposed
approach on an ambitious dataset collected over the course of one year
including more than 25k demonstration trajectories extracted from over 120km of
driving around pedestrianised areas in the city of Milton Keynes, UK. We
evaluate the resulting cost representations by showing the advantages over a
carefully manually designed cost map and, in addition, demonstrate its
robustness to systematic errors by learning precise cost-maps even in the
presence of system calibration perturbations.


title: Two Measures of Dependence

abstract:
  Two families of dependence measures between random variables are introduced.
They are based on the R\'enyi divergence of order $\alpha$ and the relative
$\alpha$-entropy, respectively, and both dependence measures reduce to
Shannon's mutual information when their order $\alpha$ is one. The first
measure shares many properties with the mutual information, including the
data-processing inequality, and can be related to the optimal error exponents
in composite hypothesis testing. The second measure does not satisfy the
data-processing inequality, but appears naturally in the context of distributed
task encoding.


title:
SXDF-ALMA 2 Arcmin^2 Deep Survey: Resolving and Characterizing the
  Infrared Extragalactic Background Light Down to 0.5 mJy

abstract:
  We present a multi-wavelength analysis of five submillimeter sources (S_1.1mm
= 0.54-2.02 mJy) that were detected during our 1.1-mm-deep continuum survey in
the SXDF-UDS-CANDELS field (2 arcmin^2, 1sigma = 0.055 mJy beam^-1) using the
Atacama Large Millimeter/submillimeter Array (ALMA). The two brightest sources
correspond to a known single-dish (AzTEC) selected bright submillimeter galaxy
(SMG), whereas the remaining three are faint SMGs newly uncovered by ALMA. If
we exclude the two brightest sources, the contribution of the ALMA-detected
faint SMGs to the infrared extragalactic background light is estimated to be ~
4.1^{+5.4}_{-3.0} Jy deg^{-2}, which corresponds to ~ 16^{+22}_{-12}% of the
infrared extragalactic background light. This suggests that their contribution
to the infrared extragalactic background light is as large as that of bright
SMGs. We identified multi-wavelength counterparts of the five ALMA sources. One
of the sources (SXDF-ALMA3) is extremely faint in the optical to near-infrared
region despite its infrared luminosity (L_IR ~ 1e12 L_sun or SFR ~ 100 M_sun
yr^{-1}). By fitting the spectral energy distributions (SEDs) at the
optical-to-near-infrared wavelengths of the remaining four ALMA sources, we
obtained the photometric redshifts (z_photo) and stellar masses (M_*): z_photo
~ 1.3-2.5, M_* ~ (3.5-9.5)e10 M_sun. We also derived their star formation rates
(SFRs) and specific SFRs (sSFRs) as ~ 30-200 M_sun yr^{-1} and ~ 0.8-2
Gyr^{-1}, respectively. These values imply that they are main-sequence
star-forming galaxies.


title: Gorenstein duality for Real spectra

abstract:
  Following Hu and Kriz, we study the $C_2$-spectra $BP\mathbb{R}\langle n
\rangle$ and $E\mathbb{R}(n)$ that refine the usual truncated Brown-Peterson
and the Johnson-Wilson spectra. In particular, we show that they satisfy
Gorenstein duality with a representation grading shift and identify their
Anderson duals. We also compute the associated local cohomology spectral
sequence in the cases $n=1$ and $2$.


title: An Equivariant Theory for the Bivariant Cuntz Semigroup

abstract:
  We provide an equivariant extension of the bivariant Cuntz semigroup
introduced in previous work for the case of compact group actions over
C*-algebras. Its functoriality properties are explored and some well-known
classification results are retrieved. Connections with crossed products are
investigated, and a concrete presentation of equivariant Cuntz homology is
provided. The theory that is here developed can be used to define the
equivariant Cuntz semigroup. We show that the object thus obtained coincides
with the recently proposed one by Gardella and Santiago, and we complement
their work by providing an open projection picture of it.


title: Betweenness centrality profiles in trees

abstract:
  Betweenness centrality of a vertex in a graph measures the fraction of
shortest paths going through the vertex. This is a basic notion for determining
the importance of a vertex in a network. The k-betweenness centrality of a
vertex is defined similarly, but only considers shortest paths of length at
most k. The sequence of k-betweenness centralities for all possible values of k
forms the betweenness centrality profile of a vertex. We study properties of
betweenness centrality profiles in trees.
  We show that for scale-free random trees, for fixed k, the expectation of
k-betweenness centrality strictly decreases as the index of the vertex
increases. We also analyze worst-case properties of profiles in terms of the
distance of profiles from being monotone, and the number of times pairs of
profiles can cross. This is related to whether k-betweenness centrality, for
small values of k, may be used instead of having to consider all shortest
paths. Bounds are given that are optimal in order of magnitude. We also present
some experimental results for scale-free random trees.


title: The Mutual Information in Random Linear Estimation

abstract:
  We consider the estimation of a signal from the knowledge of its noisy linear
random Gaussian projections, a problem relevant in compressed sensing, sparse
superposition codes or code division multiple access just to cite few. There
has been a number of works considering the mutual information for this problem
using the heuristic replica method from statistical physics. Here we put these
considerations on a firm rigorous basis. First, we show, using a Guerra-type
interpolation, that the replica formula yields an upper bound to the exact
mutual information. Secondly, for many relevant practical cases, we present a
converse lower bound via a method that uses spatial coupling, state evolution
analysis and the I-MMSE theorem. This yields, in particular, a single letter
formula for the mutual information and the minimal-mean-square error for random
Gaussian linear estimation of all discrete bounded signals.


title:
Supercurrent-induced Skyrmion dynamics and Tunable Weyl points in Chiral
  Magnet with Superconductivity

abstract:
  Recent studies show superconductivity provides new perspectives on
spintronics. We study a heterostructure composed of an s-wave superconductor
and a cubic chiral-magnet that can stabilize a topological spin texture, a
skyrmion. We propose a supercurrent-induced spin torque that originates from
the spin-orbit coupling, and we show that the spin torque can drive a skyrmion
in an efficient way that reduces Joule heating. We also study the band
structure of Bogoliubov quasiparticles and show the existence of Weyl points,
whose positions can be controlled by the direction of the magnetization. This
results in an effective magnetic field acting on the quasiparticles in the
presence spin textures. Furthermore, the tilt of the Weyl cones can also be
tuned by the strength of the spin-orbit coupling, and we propose a possible
realization of type-II Weyl points.


title:
Model order reduction approaches for infinite horizon optimal control
  problems via the HJB equation

abstract:
  We investigate feedback control for infinite horizon optimal control problems
for partial differential equations. The method is based on the coupling between
Hamilton-Jacobi-Bellman (HJB) equations and model reduction techniques. It is
well-known that HJB equations suffer the so called curse of dimensionality and,
therefore, a reduction of the dimension of the system is mandatory. In this
report we focus on the infinite horizon optimal control problem with quadratic
cost functionals. We compare several model reduction methods such as Proper
Orthogonal Decomposition, Balanced Truncation and a new algebraic Riccati
equation based approach. Finally, we present numerical examples and discuss
several features of the different methods analyzing advantages and
disadvantages of the reduction methods.


title: Resonant electron-phonon-electron interaction

abstract:
  The effect of the resonance of electron scattering energy difference and
phonon energy on the electron-phonon-electron interaction (EPEI) is studied.
Results show that the resonance of electron transition energy and phonon energy
can enhance EPEI by a magnitude of 1 to 2. Moreover, the anisotropic S-wave
electron or dx2-y2 electron can enhance resonance EPEI, and the self-energy
correction of the electron will weaken resonance EPEI. Particularly, the
asymmetrical spin-flip scattering process in k space can reduce the effect of
electronic self-energy to enhance resonance EPEI


title: New planetary and EB candidates from Campaigns 1-6 of the K2 mission

abstract:
  With only two functional reaction wheels, Kepler cannot maintain stable
pointing at its original target field and entered a new mode of observation
called K2. Our method is based on many years of experience in planet hunting
for the CoRoT mission. Due to the unstable pointing, K2 light curves present
systematics that are correlated with the target position in the CCD. Therefore,
our pipeline also includes a decorrelation of this systematic noise. Our
pipeline is optimised for bright stars for which spectroscopic follow-up is
possible. We achieve a maximum precision on 6 hours of 6 ppm. The decorrelated
light curves are searched for transits with an adapted version of the CoRoT
alarm pipeline. We present 172 planetary candidates and 327 eclipsing binary
candidates from campaigns 1, 2, 3, 4, 5 and 6 of K2. Both the planetary
candidates and eclipsing binary candidates lists are made public to promote
follow-up studies. The light curves will also be available to the community.


title: Homogenization of a semilinear heat equation

abstract:
  We consider the homogenization of a semilinear heat equation with vanishing
viscosity and with oscillating positive potential depending on $u/\varepsilon$.
According to the rate between the frequency of oscillations in the potential
and the vanishing factor in the viscosity, we obtain different regimes in the
limit evolution and we discuss the locally uniform convergence of the solutions
to the effective problem. The interesting feature of the model is that in the
strong diffusion regime the effective operator is discontinuous in the gradient
entry. We get a complete characterization of the limit solution in dimension
$n=1$, whereas in dimension $n>1$ we discuss the main properties of the
solutions to the effective problem selected at the limit and we prove
uniqueness for some classes of initial data.


title:
Discovery of WASP-113b and WASP-114b, two inflated hot-Jupiters with
  contrasting densities

abstract:
  We present the discovery and characterisation of the exoplanets WASP-113b and
WASP-114b by the WASP survey, {\it SOPHIE} and {\it CORALIE}. The planetary
nature of the systems was established by performing follow-up photometric and
spectroscopic observations. The follow-up data were combined with the
WASP-photometry and analysed with an MCMC code to obtain system parameters. The
host stars WASP-113 and WASP-114 are very similar. They are both early G-type
stars with an effective temperature of $\sim 5900\,$K, [Fe/H]$\sim 0.12$ and
$T_{\rm eff}$ $\sim 4.1$dex. However, WASP-113 is older than WASP-114. Although
the planetary companions have similar radii, WASP-114b is almost 4 times
heavier than WASP-113b. WASP-113b has a mass of $0.48\,$ $\mathrm{M}_{\rm Jup}$
and an orbital period of $\sim 4.5\,$days; WASP-114b has a mass of $1.77\,$
$\mathrm{M}_{\rm Jup}$ and an orbital period of $\sim 1.5\,$days. Both planets
have inflated radii, in particular WASP-113 with a radius anomaly of
$\Re=0.35$. The high scale height of WASP-113b ($\sim 950$ km ) makes it a good
target for follow-up atmospheric observations.


title: Calorimetric measurement of work for a driven harmonic oscillator

abstract:
  A calorimetric measurement has recently been proposed as a promising
technique to measure thermodynamic quantities in a dissipative superconducting
qubit. These measurements rely on the fact that the system is projected into
energy eigenstates whenever energy is exchanged with the environment. This
requirement imposes a restriction on the class of systems that can be measured
in this way. Here we extend the calorimetric protocol to the measurement of a
driven quantum harmonic oscillator. We employ a scheme based on the two-level
approximation to define a new work quantity and show how its statistics relates
to the standard two-measurement protocol. We find that for the average work the
two-level approximation holds in the underdamped regime for short driving times
and, in the overdamped regime, for any driving time. However, this
approximation fails for the variance and higher moments of work at finite
temperatures. Furthermore, we show how to relate the work statistics obtained
through this scheme to the work statistics given by the two-measurement
protocol.


title: c-number Quantum Generalised Langevin Equation for an open system

abstract:
  We derive a $c-$number Generalised Langevin Equation (GLE) describing the
evolution of the expectation values $\left\langle x_{i}\right\rangle_{t}$ of
the atomic position operators $x_{i}$ of an open system. The latter is coupled
linearly to a harmonic bath kept at a fixed temperature. The equations of
motion contain a non-Markovian friction term with the classical kernel {[}L.
Kantorovich - PRB 78, 094304 (2008){]} and a zero mean \emph{non-Gaussian}
random force with correlation functions that depend on the initial preparation
of the open system. We used a density operator formalism without assuming that
initially the combined system was decoupled. The only approximation made in
deriving quantum GLE consists in assuming that the Hamiltonian of the open
system at time $t$ can be expanded up to the second order with respect to
operators of atomic displacements $u_{i}=x_{i}-\left\langle
x_{i}\right\rangle_{t}$ in the open system around their exact atomic positions
$\left\langle x_{i}\right\rangle_{t}$ (the "harmonisation" approximation). The
noise is introduced to ensure that sampling many quantum GLE trajectories
yields exactly the average one. An explicit expression for the pair correlation
function of the noise, consistent with the classical limit, is also proposed.
Unlike the usually considered quantum operator GLE, the proposed $c-$number
quantum GLE can be used in direct molecular dynamic simulations of open systems
under general equilibrium or non-equilibrium conditions.


title: Exclusive meson production at HERMES

abstract:
  The data were accumulated with the HERMES forward spectrometer using the 27.6
GeV longitudinally polarized electron or positron beam of HERA. Exclusive
electroproduction of $\omega$ mesons on unpolarized hydrogen and deuterium
targets is studied in the kinematic region of $Q^2>1.0$ GeV$^2$, 3.0 GeV $< W
<$ 6.3 GeV, and $-t'< 0.2 $ GeV$^{2}$, while for $\rho^0$-meson production on a
transversely polarized hydrogen target $-t'< 0.4$ GeV$^{2}$ is used.
  Spin-density matrix elements for $\omega$ production are presented in
projections of $Q^2$ or $-t'$, while the ratios of the helicity amplitudes for
the reaction $\gamma^*+p \to \rho^0+p$ are obtained in the entire kinematic
region. The usage of the transversely polarized target allows for the first
time the extraction of the ratios of certain nucleon-helicity-flip amplitudes
to the natural-parity exchange amplitude $T_{0\frac{1}{2}0\frac{1}{2}}$ without
the nucleon-helicity flip describing the longitudinal $\rho^0$-meson production
by the longitudinal virtual photon. Violation of $s$-channel helicity
conservation is observed for both mesons.
  A dominant contribution from unnatural-parity exchange (UPE) is established
for special combinations of the $\omega$ spin-density matrix elements. For
$\rho^0$-meson production, the UPE amplitude without the nucleon-helicity flip,
$U_{1\frac{1}{2}1\frac{1}{2}}$, is shown to be the largest UPE amplitude. Good
agreement is found between the HERMES data on $\omega$ production on the proton
and results of the perturbative QCD-inspired Goloskokov-Kroll model that
includes pion-pole contribution.


title:
Bulk-edge correspondence, spectral flow and Atiyah-Patodi-Singer theorem
  for the Z2-invariant in topological insulators

abstract:
  We study the bulk-edge correspondence in topological insulators by taking
Fu-Kane spin pumping model as an example. We show that the Kane-Mele invariant
in this model is Z2 invariant modulo the spectral flow of a single-parameter
family of 1+1-dimensional Dirac operators with a global boundary condition
induced by the Kramers degeneracy of the system. This spectral flow is defined
as an integer which counts the difference between the number of eigenvalues of
the Dirac operator family that flow from negative to non-negative and the
number of eigenvalues that flow from non-negative to negative. Since the bulk
states of the insulator are completely gapped and the ground state is assumed
being no more degenerate except the Kramers, they do not contribute to the
spectral flow and only edge states contribute to. The parity of the number of
the Kramers pairs of gapless edge states is exactly the same as that of the
spectral flow. This reveals the origin of the edge-bulk correspondence, i.e.,
why the edge states can be used to characterize the topological insulators.
Furthermore, the spectral flow is related to the reduced eta-invariant and thus
counts both the discrete ground state degeneracy and the continuous gapless
excitations, which distinguishes the topological insulator from the
conventional band insulator even if the edge states open a gap due to a strong
interaction between edge modes. We emphasize that these results are also valid
even for a weak disordered and/or weak interacting system. The higher spectral
flow to categorize the higher-dimensional topological insulators are expected.


title: Strengthening Hardness Results to 3-Connected Planar Graphs

abstract:
  In this paper we extend some classical NP-hardness results from the class of
2-connected planar graphs to subclasses of 3-connected planar graphs. The
reduction are partly based on a new graph augmentation, which may be of
independent interest.


title: On the Complexity of Realizing Facial Cycles

abstract:
  We study the following combinatorial problem. Given a planar graph $G=(V,E)$
and a set of simple cycles $\mathcal C$ in $G$, find a planar embedding
$\mathcal E$ of $G$ such that the number of cycles in $\mathcal C$ that bound a
face in $\mathcal E$ is maximized. We establish a tight border of tractability
for this problem in biconnected planar graphs by giving conditions under which
the problem is NP-hard and showing that relaxing any of these conditions makes
the problem polynomial-time solvable. Moreover, we give a $2$-approximation
algorithm for series-parallel graphs and a $(4+\varepsilon)$-approximation for
biconnected planar graphs.


title:
The quantum nature of the superconducting hydrogen sulfide at finite
  temperatures

abstract:
  H$_3$S is believed to the most possible high-temperature superconducting
($T_{\text{c}}$) phase of hydrogen sulfide at $\sim$200 GPa. It's isotope
substitution of hydrogen (H) by deuterium (D), however, shows an anomalous
$T_{\text{c}}$ decrease of $\sim$100 K at 140 to 160 GPa, much larger than the
Bardeen-Cooper-Schrieffer theory prediction. Using ab initio path-integral
molecular dynamics (PIMD), we show that the nuclear quantum effects (NQEs)
influence the structures of H$_3$S and D$_3$S differently at finite
temperatures and the interval when H$_3$S possesses the symmetric high
$T_{\text{c}}$ structure while D$_3$S does not is in agreement with, though
their absolute values are lower than experiments. This is consistent with an
earlier theoretical study using the stochastic self-consistent harmonic
approximation method in descriptions of the nuclei at 0 K.The remaining
discrepancy can be substantially improved when the electronic structures are
calculated using a hybrid function. Our study presents a simple picture to
interpret the isotope dependent of $T_{\text{c}}$ and emphasizes the quantum
nature in the high-pressure hydrogen sulfide system.


title:
Toward an integrated workforce planning framework using structured
  equations

abstract:
  Strategic Workforce Planning is a company process providing best in class,
economically sound, workforce management policies and goals. Despite the
abundance of literature on the subject, this is a notorious challenge in terms
of implementation. Reasons span from the youth of the field itself to broader
data integration concerns that arise from gathering information from financial,
human resource and business excellence systems. This paper aims at setting the
first stones to a simple yet robust quantitative framework for Strategic
Workforce Planning exercises. First a method based on structured equations is
detailed. It is then used to answer two main workforce related questions: how
to optimally hire to keep labor costs flat? How to build an experience
constrained workforce at a minimal cost?


title: Reconceiling the orbital and physical properties of the martian moons

abstract:
  The origin of Phobos and Deimos is still an open question. Currently, none of
the three proposed scenarios for their origin (intact capture of two distinct
outer solar system small bodies, co-accretion with Mars, and accretion within
an impact-generated disk) is able to reconcile their orbital and physical
properties. Here, we investigate the expected mineralogical composition and
size of the grains from which the moons once accreted assuming they formed
within an impact-generated accretion disk. A comparison of our results with the
present day spectral properties of the moons allows us to conclude that their
building blocks cannot originate from a magma phase, thus preventing their
formation in the innermost part of the disk. Instead, gas-to-solid condensation
of the building blocks in the outer part of an extended gaseous disk is found
as a possible formation mechanism as it does allow reproducing both the
spectral and physical properties of the moons. Such a scenario may finally
reconcile their orbital and physical properties alleviating the need to invoke
an unlikely capture scenario to explain their physical properties.


title: Coupling of three-spin qubits to their electric environment

abstract:
  We investigate the behavior of qubits consisting of three electron spins in
double and triple quantum dots subject to external electric fields. Our model
includes two independent bias parameters, $\varepsilon$ and $\varepsilon_{M}$,
which both couple to external electromagnetic fields and can be controlled by
gate voltages applied to the quantum dot structures. By varying these
parameters one can switch the qubit type by shifting the energies in the single
quantum dots thus changing the electron occupancy in each dot. Starting from
the asymmetric resonant (ARX) exchange qubit with a (2,0,1) and (1,0,2) charge
admixture one can smoothly cross over to the resonant exchange (RX) qubit with
a detuned (1,1,1) charge configuration, and to the exchange-only (EO) qubit
with the same charge configuration but equal energy levels down to the hybrid
qubits with (1,2,0) and (0,2,1) charge configurations. Here, ($l,m,n$)
describes a configuration with $l$ electrons in the left dot, $m$ electrons in
the center dot, and $n$ electrons in the right dot. We first focus on random
electromagnetic field fluctuations, i.e., "charge noise", at each quantum dot
resulting in dephasing of the qubit and provide a complete map of the resulting
dephasing time as a function of the bias parameters. We pay special attention
to the so-called sweet spots and double sweet spots of the system which are
least susceptible to noise. In the second part we investigate the coupling of
the qubit system to the coherent quantized electromagnetic field in a
superconducting strip-line cavity and also provide a complete map of the
coupling strength as a function of the bias parameters. We analyze the
asymmetric qubit-cavity coupling via $\varepsilon$ and the symmetric coupling
via $\varepsilon_{M}$.


title: Breaking the temporal resolution limit by superoscillating optical beats

abstract:
  Band-limited functions can oscillate locally at an arbitrarily fast rate
through an interference phenomenon known as superoscillations. Using an optical
pulse with a superoscillatory envelope we experimentally break the temporal
Fourier-transform limit having a temporal feature which is approximately three
times shorter than the duration of a transform-limited Gaussian pulse having a
comparable bandwidth while maintaining $29.5\%$ visibility. Numerical
simulations demonstrate the ability of such signals to achieve temporal
super-resolution.


title:
Spectropolarimetry of superluminous supernovae: insight into their
  geometry

abstract:
  We present the first spectropolarimetric observations of a hydrogen-free
superluminous supernova at z=0.1136, namely SN 2015bn. The transient shows
significant polarization at both the observed epochs: one 24 days before
maximum light in the rest-frame, and the subsequent at 27 days after peak
luminosity. Analysis of the Q-U plane suggests the presence of a dominant axis
and no physical departure from the main axis at either epoch. The polarization
spectrum along the dominant axis is characterized by a strong wavelength
dependence and an increase in the signal from the first to the second epoch. We
use a Monte Carlo code to demonstrate that these properties are consistent with
a simple toy model that adopts an axi-symmetric ellipsoidal configuration for
the ejecta. We find that the wavelength dependence of the polarisation is
possibly due to a strong wavelength dependence in the line opacity, while the
higher level of polarisation at the second epoch is a consequence of the
increase in the asphericity of the inner layers of the ejecta or the fact that
the photosphere recedes into less spherical layers. The geometry of the
superluminous supernova results similar to those of stripped-envelope core
collapse SNe connected with GRB, while the overall evolution of the ejecta
shape could be consistent with a central engine.


title:
Systematic theoretical analysis of dual-parameters RF readout by a novel
  LC-type passive sensor

abstract:
  This paper systematically studied the simultaneous measurement of two
parameters by a LC-type passive sensor from the theoretical perspective. Based
on the lumped circuit model of the typical LC-type passive dual-parameter
sensor system, the influencing factors of the signal strength of the sensor as
well as the influencing factors of signal crosstalk were both analyzed. It is
found that the influencing factors of the RF readout signal strength of the
sensor are mainly quality factors (Q factors) of the LC tanks, coupling
coefficients, and the resonant frequency interval of the two LC tanks. And the
influencing factors of the signal crosstalk are mainly coupling coefficient
between the sensor inductance coils and the resonant frequency interval of the
two LC tanks. The specific influence behavior of corresponding influencing
factors on the signal strength and crosstalk is illustrated by a series of
curves from numerical results simulated by using MATLAB software. Additionally,
a decoupling scheme for solving the crosstalk problem algorithmically was
proposed and a corresponding function was derived out. Overall, the theoretical
analysis conducted in this work can provide design guidelines for making the
dual-parameter LC-type passive sensor useful in practical applications.


title: Lexical Based Semantic Orientation of Online Customer Reviews and Blogs

abstract:
  Rapid increase in internet users along with growing power of online review
sites and social media has given birth to sentiment analysis or opinion mining,
which aims at determining what other people think and comment. Sentiments or
Opinions contain public generated content about products, services, policies
and politics. People are usually interested to seek positive and negative
opinions containing likes and dislikes, shared by users for features of
particular product or service. This paper proposed sentence-level lexical based
domain independent sentiment classification method for different types of data
such as reviews and blogs. The proposed method is based on general lexicons
i.e. WordNet, SentiWordNet and user defined lexical dictionaries for semantic
orientation. The relations and glosses of these dictionaries provide solution
to the domain portability problem. The method performs better than word and
text level corpus based machine learning methods for semantic orientation. The
results show the proposed method performs better as it shows precision of 87%
and83% at document and sentence levels respectively for online comments.


title:
Post-Newtonian parameter $\gamma$ for multiscalar-tensor gravity with a
  general potential

abstract:
  We compute the parametrized post-Newtonian parameter $\gamma$ in the case of
a static point source for multiscalar-tensor gravity with completely general
nonderivative couplings and potential in the Jordan frame. Similarly to the
single massive field case $\gamma$ depends exponentially on the distance from
the source and is determined by the length of a vector of non-minimal coupling
in the space of scalar fields and its orientation relative to the mass
eigenvectors. Using data from the Cassini tracking experiment, we estimate
bounds on a general theory with two scalar fields. Our formalism can be
utilized for a wide range of models, which we illustrate by applying it to
nonminimally coupled Higgs SU(2) doublet, general hybrid metric-Palatini
gravity, linear ($\Box^{-1}$) and quadratic ($\Box^{-2}$) nonlocal gravity.


title: Optical design of a multi-resolution, single shot spectrograph

abstract:
  Multi-object or integral field spectrographs are recognized techniques for
achieving simultaneous spectroscopic observations of different or extended sky
objects with a high multiplex factor. In this communication is described a
complementary approach for realizing similar measurements under different
spectral resolutions at the same time. We describe the basic principle of this
new type of spectrometer, that is based on the utilization of an optical pupil
slicer. An optical design inspired from an already studied instrument is then
presented and commented for the sake of illustration. Technical issues about
the pupil slicer and diffractive components are also discussed. We finally
conclude on the potential advantages and drawbacks of the proposed system.


title:
Control of magnon-photon coupling strength in a planar resonator/YIG
  thin film configuration

abstract:
  A systematic study of the coupling at room temperature between ferromagnetic
resonance (FMR) and a planar resonator is presented. The chosen magnetic
material is a ferrimagnetic insulator (Yttrium Iron Garnet: YIG) which is
positioned on top of a stop band (notch) filter based on a stub line
capacitively coupled to a 50 $\Omega$ microstrip line resonating at 4.731 GHz.
Control of the magnon-photon coupling strength is discussed in terms of the
microwave excitation configuration and the YIG thickness from 0.2 to 41 $\mu$m.
From the latter dependence, we extract a single spin-photon coupling of
g$_{0}$/2$\pi$=162$\pm$6 mHz and a maximum of an effective coupling of 290 MHz.


title: Momentum broadening in unstable quark-gluon plasma

abstract:
  Quark-gluon plasma produced at the early stage of ultrarelativistic heavy ion
collisions is unstable, if weakly coupled, due to the anisotropy of its
momentum distribution. Chromomagnetic fields are spontaneously generated and
can reach magnitudes much exceeding typical values of the fields in
equilibrated plasma. We consider a high energy test parton traversing an
unstable plasma that is populated with strong fields. We study the momentum
broadening parameter $\hat q$ which determines the radiative energy loss of the
test parton. We develop a formalism which gives $\hat q$ as the solution of an
initial value problem, and we focus on extremely oblate plasmas which are
physically relevant for relativistic heavy ion collisions. The parameter $\hat
q$ is found to be strongly dependent on time. For short times it is of the
order of the equilibrium value, but at later times $\hat q$ grows exponentially
due to the interaction of the test parton with unstable modes and becomes much
bigger than the value in equilibrium. The momentum broadening is also strongly
directionally dependent and is largest when the test parton velocity is
transverse to the beam axis. Consequences of our findings for the phenomenology
of jet quenching in relativistic heavy ion collisions are briefly discussed.


title:
Nuclear Magnetic Resonance Reveals Disordered Level-Crossing Physics in
  the Bose-Glass Regime of the Br-doped
  Ni(Cl$_{1-x}$Br$_x$)$_2$-4SC(NH$_2$)$_2$ Compound at a High Magnetic Field

abstract:
  By measuring the nuclear magnetic resonance (NMR) 1/T_1 relaxation rate in
the Br (bond) doped DTN compound, Ni(Cl(1-x)Br_x)2-4SC(NH2)2 (DTNX), we show
that the low-energy spin dynamics of its high magnetic field "Bose-glass"
regime is dominated by a strong peak of spin fluctuations found at the nearly
doping-independent position H* = 13.6 T. From its temperature and field
dependence we conclude that this corresponds to a level crossing of the energy
levels related to the doping-induced impurity states. Observation of the local
NMR signal from the spin adjacent to the doped Br allowed us to fully
characterize this impurity state. We have thus quantified a microscopic
theoretical model that paves the way to better understanding of the Bose-glass
physics in DTNX, as revealed in the related theoretical study [M. Dupont, S.
Capponi, and N. Laflorencie, Phys. Rev. Lett. 118, 067204 (2017),
arXiv:1610.05136].


title:
A Factor-Graph Approach to Algebraic Topology, With Applications to
  Kramers--Wannier Duality

abstract:
  Algebraic topology studies topological spaces with the help of tools from
abstract algebra. The main focus of this paper is to show that many concepts
from algebraic topology can be conveniently expressed in terms of (normal)
factor graphs. As an application, we give an alternative proof of a classical
duality result of Kramers and Wannier, which expresses the partition function
of the two-dimensional Ising model at a low temperature in terms of the
partition function of the two-dimensional Ising model at a high temperature.
Moreover, we discuss analogous results for the three-dimensional Ising model
and the Potts model.


title: Observing Coherence Effects in an Overdamped Quantum System

abstract:
  It is usually considered that the spectrum of an optical cavity coupled to an
atomic medium does not exhibit a normal-mode splitting unless the system
satisfies the strong coupling condition, meaning the Rabi frequency of the
coherent coupling exceeds the decay rates of atom and cavity excitations. Here
we show that this need not be the case, but depends on the way in which the
coupled system is probed. Measurements of the reflection of a probe laser from
the input mirror of an overdamped cavity reveal an avoided crossing in the
spectrum which is not observed when driving the atoms directly and measuring
the Purcell-enhanced cavity emission. We understand these observations by
noting a formal correspondence with electromagnetically-induced transparency of
a three-level atom in free space, where our cavity acts as the absorbing medium
and the coupled atoms play the role of the control field.


title:
The behaviour of magnetoacoustic waves in the neighbourhood of a
  two-dimensional null point: initially cylindrically-symmetric perturbations

abstract:
  The propagation of magnetoacoustic waves in the neighbourhood of a 2D null
point is investigated for both $\beta=0$ and $\beta \neq 0$ plasmas. Previous
work has shown that the Alfv\'en speed, here $v_A \propto r$, plays a vital
role in such systems and so a natural choice is to switch to polar coordinates.
For the $\beta=0$ plasma, we derive an analytical solution for the behaviour of
the fast magnetoacoustic wave in terms of the Klein-Gordon equation. We also
solve the system with a semi-analytical WKB approximation which shows that the
$\beta=0$ wave focuses on the null and contracts around it but, due to
exponential decay, never reaches the null in a finite time. For the $\beta \neq
0$ plasma, we solve the system numerically and find the behaviour to be similar
to that of the $\beta=0$ system at large radii, but completely different close
to the null. We show that for an initially cylindrically-symmetric fast
magnetoacoustic wave perturbation, there is a decrease in wave speed along the
separatrices and so the perturbation starts to take on a quasi-diamond shape;
with the corners located along the separatrices. This is due to the growth in
pressure gradients that reach a maximum along the separatrices, which in turn
reduces the acceleration of the fast wave along the separatrices leading to a
deformation of the wave morphology.


title: Delayed Choice, Complementarity, Entanglement and Measurement

abstract:
  It is well known that Wheeler proposed several delayed choice experiments in
order to show the impossibility to speak of the way a quantum system behaves
before being detected. In a double-slit experiment, when do photons decide to
travel by one way or by two ways? Delayed choice experiments seem to indicate
that, strangely, it is possible to change the decision of the photons until the
very last moment before they are detected. This led Wheeler to his famous
sentence: No elementary quantum phenomenon is a phenomenon until it is a
registered phenomenon, brought to a close by an irreversible act of
amplification. Nevertheless some authors wrote that backward in time effects
were needed to explain these results. I will show that in delayed choice
experiments involving only one particle, a simple explanation is possible
without invoking any backward in time effect. Delayed choice experiments
involving entangled particles such as the so called quantum eraser can also be
explained without invoking any backward in time effect but I will argue that
these experiments cannot be accounted for so simply because they rise the whole
problem of knowing what a measurement and a collapse are. A previously
presented interpretation, Convivial Solipsism, is a natural framework for
giving a simple explanation of these delayed choice experiments with entangled
particles. In this paper, I show how Convivial Solipsism helps clarifying the
puzzling questions raised by the collapse of the wave function of entangled
systems.


title: Creating band gaps in periodic media

abstract:
  We identify explicit conditions on geometry and material contrast for
creating band gaps in 2-d photonic and 3-d acoustic crystals. This approach is
novel and makes use of the electro-static and quasi-periodic source free
resonances of the crystal. The source free modes deliver a spectral
representation for solution operators associated with propagation of
electromagnetic and acoustic waves inside periodic high contrast media. An
accurate characterization of the quasi-periodic and electrostatic resonance
spectrum in terms of the shape and geometry of the scatters is possible. This
information together with the Dirichlet and a Neumann like spectra associated
with the inclusions deliver conditions sufficient for opening band gaps at
finite contrast. The theory provides a systematic means for the identification
of photonic and phononic band gaps within a specified frequency range.


title: Security of quantum key distribution with multiphoton components

abstract:
  Most qubit-based quantum key distribution (QKD) protocols extract the secure
key merely from single-photon component of the attenuated lasers. However, with
the Scarani-Acin-Ribordy-Gisin 2004 (SARG04) QKD protocol, the unconditionally
secure key can be extracted from the two-photon component by modifying the
classical post-processing procedure in the BB84 protocol. Employing the merits
of SARG04 QKD protocol and six-state preparation, one can extract secure key
from the components of single photon up to four photons. In this paper, we
provide the exact relations between the secure key rate and the bit error rate
in a six-state SARG04 protocol with single-photon, two-photon, three-photon,
and four-photon sources. By restricting the mutual information between the
phase error and bit error, we obtain a higher secure bit error rate threshold
of the multiphoton components than previous works. Besides, we compare the
performances of the six-state SARG04 with other prepare-and-measure QKD
protocols using decoy states.


title: On very short and intense laser-plasma interactions

abstract:
  We briefly report on some results regarding the impact of very short and
intense laser pulses on a cold, low-density plasma initially at rest, and the
consequent acceleration of plasma electrons to relativistic energies. Locally
and for short times the pulse can be described by a transverse plane
electromagnetic travelling-wave and the motion of the electrons by a purely
Magneto-Fluido-Dynamical (MFD) model with a very simple dependence on the
transverse electromagnetic potential, while the ions can be regarded as at
rest; the Lorentz-Maxwell and continuity equations are reduced to the Hamilton
equations of a Hamiltonian system with 1 degree of freedom, in the case of a
plasma with constant initial density, or a collection of such systems
otherwise. We can thus describe both the well-known "wakefield" behind the
pulse and the recently predicted "slingshot effect", i.e. the backward
expulsion of high energy electrons just after the laser pulse has hit the
surface of the plasma.


title:
Poset structures on (m + 2)-angulations and polynomial bases of the
  quotient by G^m -quasisymmetric functions

abstract:
  For integers m, n $\ge$ 1, we describe a bijection sending dissections of the
(mn + 2)-regular polygon into (m + 2)-sided polygons to a new basis of the
quotient of the polynomial algebra in mn variables by an ideal generated by
some kind of higher quasi-symmetric functions. We show that divisibility of the
basis elements corresponds to a new partial order on dissections, which is
studied in some detail.


title: Laboratory rotational ground state transitions of NH$_3$D$^+$ and CF$^+$

abstract:
  Aims. This paper reports accurate laboratory frequencies of the rotational
ground state transitions of two astronomically relevant molecular ions, NH3D+
and CF+. Methods. Spectra in the millimeter-wave band were recorded by the
method of rotational state-selective attachment of He-atoms to the molecular
ions stored and cooled in a cryogenic ion trap held at 4 K. The lowest
rotational transition in the A state (ortho state) of NH$_3$D$^+$ ($J_K = 1_0 -
0_0$), and the two hyperfine components of the ground state transition of
CF$^+$($J = 1 - 0$) were measured with a relative precision better than
$10^{-7}$. Results. For both target ions the experimental transition
frequencies agree with recent observations of the same lines in different
astronomical environments. In the case of NH$_3$D$^+$ the high-accuracy
laboratory measurements lend support to its tentative identification in the
interstellar medium. For CF$^+$ the experimentally determined hyperfine
splitting confirms previous quantum-chemical calculations and the intrinsic
spectroscopic nature of a double-peaked line profile observed in the $J = 1 -
0$ transition towards the Horsehead PDR.


title: Sur la conjecture de Collatz

abstract:
  We give a generalization of Collatz conjecture or 3n+1 problem on 2-adic
completion of Q. A isometric of $Q_2$ provides information on the average
behavior of the firsts terms of the sequence according to the class of $u_0$
modulo $2^m$. A generalisation from the pair (2,3) to the pair (p,q) seems
possible under the assumption $q^{p-1}<p^p$.


title: A game theoretic approach to a peer-to-peer cloud storage model

abstract:
  Classical cloud storage based on external data providers has been recognized
to suffer from a number of drawbacks. This is due to its inherent centralized
architecture which makes it vulnerable to external attacks, malware, technical
failures, as well to the large premium charged for business purposes. In this
paper, we propose an alternative distributed peer-to-peer cloud storage model
which is based on the observation that the users themselves often have
available storage capabilities to be offered in principle to other users. Our
set-up is that of a network of users connected through a graph, each of them
being at the same time a source of data to be stored externally and a possible
storage resource. We cast the peer-to-peer storage model to a Potential Game
and we propose an original decentralized algorithm which makes units interact,
cooperate, and store a complete back up of their data on their connected
neighbors. We present theoretical results on the algorithm as well a good
number of simulations which validate our approach.


title:
Dynamical density functional theory for orientable colloids including
  inertia and hydrodynamic interactions

abstract:
  Over the last few decades, classical density-functional theory (DFT) and its
dynamic extensions (DDFTs) have become powerful tools in the study of colloidal
fluids. Recently, previous DDFTs for spherically-symmetric particles have been
generalised to take into account both inertia and hydrodynamic interactions,
two effects which strongly influence non-equilibrium properties. The present
work further generalises this framework to systems of anisotropic particles.
Starting from the Liouville equation and utilising Zwanzig's
projection-operator techniques, we derive the kinetic equation for the Brownian
particle distribution function, and by averaging over all but one particle, a
DDFT equation is obtained. Whilst this equation has some similarities with
DDFTs for spherically-symmetric colloids, it involves a
translational-rotational coupling which affects the diffusivity of the
(asymmetric) particles. We further show that, in the overdamped (high friction)
limit, the DDFT is considerably simplified and is in agreement with a previous
DDFT for colloids with arbitrary shape particles.


title: Sterile Neutrino portal to Dark Matter II: Exact Dark symmetry

abstract:
  We analyze a simple extension of the Standard Model (SM) with a dark sector
composed of a scalar and a fermion, both singlets under the SM gauge group but
charged under a dark sector symmetry group. Sterile neutrinos, which are
singlets under both groups, mediate the interactions between the dark sector
and the SM particles, and generate masses for the active neutrinos via the
seesaw mechanism. We explore the parameter space region where the observed Dark
Matter relic abundance is determined by the annihilation into sterile
neutrinos, both for fermion and scalar Dark Matter particles. The scalar Dark
Matter case provides an interesting alternative to the usual Higgs portal
scenario. We also study the constraints from direct Dark Matter searches and
the prospects for indirect detection via sterile neutrino decays to leptons,
which may be able to rule out Dark Matter masses below and around 100 GeV.


title:
Simulating terahertz quantum cascade lasers: Trends from samples from
  different labs

abstract:
  We present a systematic comparison of the results from our non-equilibrium
Green's function formalism with a large number of AlGaAs-GaAs terahertz quantum
cascade lasers previously published in the literature. Employing identical
material and simulation parameters for all samples, we observe that
discrepancies between measured and calculated peak currents are similar for
samples from a given group. This suggests that the differences between
experiment and theory are partly due to a lacking reproducibility for devices
fabricated at different laboratories. Varying the interface roughness height
for different devices, we find that the peak current under lasing operation
hardly changes, so that differences in interface quality appear not to be the
sole reason for the lacking reproducibility.