title:
Using content features to enhance performance of user-based
  collaborative filtering performance of user-based collaborative filtering

abstract:
  Content-based and collaborative filtering methods are the most successful
solutions in recommender systems. Content based method is based on items
attributes. This method checks the features of users favourite items and then
proposes the items which have the most similar characteristics with those
items. Collaborative filtering method is based on the determination of similar
items or similar users, which are called item-based and user-based
collaborative filtering, respectively.In this paper we propose a hybrid method
that integrates collaborative filtering and content-based methods. The proposed
method can be viewed as user-based Collaborative filtering technique. However
to find users with similar taste with active user, we used content features of
the item under investigation to put more emphasis on users rating for similar
items. In other words two users are similar if their ratings are similar on
items that have similar context. This is achieved by assigning a weight to each
rating when calculating the similarity of two users.We used movielens data set
to access the performance of the proposed method in comparison with basic
user-based collaborative filtering and other popular methods.


title: Open Quantum Walks: a short introduction

abstract:
  The concept of open quantum walks (OQW), quantum walks exclusively driven by
the interaction with the external environment, is reviewed. OQWs are formulated
as discrete completely positive maps on graphs. The basic properties of OQWs
are summarised and new examples of OQWs on $\mathbb{Z}$ and their simulation by
means of quantum trajectories are presented.


title: Analysis of dilepton angular distributions in a parity breaking medium

abstract:
  We investigate how local parity breaking (LPB) due to large topological
fluctuations may affect hadron physics. A distorted dispersion relation is
derived for the lightest vector mesons $\rho$ and $\omega$. They are
characterised by a mass splitting depending on their polarization. We present a
detailed analysis of the angular distribution associated to the lepton pairs
created from these mesons searching for polarization dependencies. Two angular
variables are found to carry the main information related to the parity
breaking effect. Possible signatures for experimental detection of local parity
breaking that could potentially be seen by the PHENIX and STAR collaborations
are discussed.


title:
An Algorithmic Framework for Computing Validation Performance Bounds by
  Using Suboptimal Models

abstract:
  Practical model building processes are often time-consuming because many
different models must be trained and validated. In this paper, we introduce a
novel algorithm that can be used for computing the lower and the upper bounds
of model validation errors without actually training the model itself. A key
idea behind our algorithm is using a side information available from a
suboptimal model. If a reasonably good suboptimal model is available, our
algorithm can compute lower and upper bounds of many useful quantities for
making inferences on the unknown target model. We demonstrate the advantage of
our algorithm in the context of model selection for regularized learning
problems.


title: Intelligent User Interface in Fuzzy Environment

abstract:
  Human-Computer Interaction with the traditional User Interface is done using
a specified in advance script dialog menu, mainly based on human intellect and
unproductive use of navigation. This approach does not lead to making
qualitative decision in control systems, where the situations and processes
cannot be structured in advance. Any dynamic changes in the controlled business
process (as example, in organizational unit of the information fuzzy control
system) make it necessary to modify the script dialogue in User Interface. This
circumstance leads to a redesign of the components of the User Interface and of
the entire control system. In the Intelligent User Interface, where the dialog
situations are unknown in advance, fuzzy structured and artificial intelligence
is crucial, the redesign described above is impossible. To solve this and other
problems, we propose the data, information and knowledge based technology of
Smart/ Intelligent User Interface (IUI) design, which interacts with users and
systems in natural and other languages, utilizing the principles of Situational
Control and Fuzzy Logic theories, Artificial Intelligence, Linguistics,
Knowledge Base technologies and others. The proposed technology of IUI design
is defined by multi-agents of Situational Control and of data, information and
knowledge, modelling of Fuzzy Logic Inference, Generalization, Representation
and Explanation of knowledge, Planning and Decision-making, Dialog Control,
Reasoning and Systems Thinking, Fuzzy Control of organizational unit in
real-time, fuzzy conditions, heterogeneous domains, and multi-lingual
communication under uncertainty and in Fuzzy Environment.


title: Nonextensive statistical dynamics applied to wall turbulence

abstract:
  We apply a formalism of nonextensive statistical mechanics to experimental
wall turbulence data, for the first time to our knowledge. Wind tunnel data for
velocity differences a streamwise distance $r$ apart are compared to the
prediction from theory as developed by Beck. The simplest theory, in which all
free parameters are removed, is found to reproduce statistics for the
wall-normal velocity component remarkably well, even for $r$ well beyond the
corresponding integral scale, while the corresponding description of the
streamwise velocity fluctuations is reasonable at separations below the
integral scale. A least-squares 2-parameter fit is performed, and the
dependence of the optimum parameter values on wall separation and $r$ is
analysed. Both parameters are found to be approximately independent of
wall-separation in the logarithmic sub-layer.


title: Phase Instability as a Source of Modal Dynamics in Semiconductor Lasers

abstract:
  Thanks to a new derivation of the fundamental equations governing multimode
dynamics for a semiconductor laser near its threshold, we identify regimes of
existence of a pure phase instability (and of a mixed phase-amplitude
turbulence regime) which give an alternative satisfactory interpre- tation of
the deterministic multimode dynamics observed in some devices. The existence of
intrinsic noise generated by the phase instability reconciles in the same
description the deterministic and random features of the semiconductor
dynamics.


title:
Thermal effects on the sudden changes and freezing of correlations
  between remote atoms in cavity QED network

abstract:
  We investigate the thermal effects on the sudden changes and freezing of the
quantum and classical correlations of remote qubits in a cavity quantum
electrodynamics (CQED) network with losses. We find that the detrimental effect
of the thermal reservoirs on the system can be compensated via an efficient
coupling of the fiber connecting the two cavities of the system. Furthermore,
for certain initial conditions, we find a double sudden transitions in the
dynamics of Bures geometrical quantum discord. The second transition tends to
disappear at a critical temperature, hence freezing the discord. Finally, we
discuss some ideas of the experimental realization of the present proposal.


title:
Measuring Quasi-Static and Kinetic Coefficient of Restitution
  Simultaneously using Levitation Mass Method: Experiment and Simulation

abstract:
  Observed peaks in a levitation mass method (LMM), which are usually addressed
to signal noise, are discussed in this work. This phenomenon arises due to
bounce from plate which is collided by moving part in LMM measurement system.
Normally, the moving part and the plate stick very good after their first
contact. Simulation using molecular dynamics (MD) method is performed to prove
the bounce prognosis.


title: Accidental degeneracy of double Dirac cones in a phononic crystal

abstract:
  Artificial honeycomb lattices with Dirac cone dispersion provide a
macroscopic platform to study the massless Dirac quasiparticles and their novel
geometric phases. In this paper, a quadruple-degenerate state is achieved at
the center of Brillouin zone (BZ) in a two-dimensional honeycomb lattice
phononic crystal, which is a result of accidental degeneracy of two
double-degenerate states. In the vicinity of the quadruple-degenerate state,
the dispersion relation is linear. Such quadruple degeneracy is analyzed by
rigorous representation theory of groups. Using method, a reduced Hamiltonian
is obtained to describe the linear Dirac dispersion relations of such
quadruple-degenerate state, which is well consistent with the simulation
results. Near such accidental degeneracy, we observe some unique wave
propagating properties, such as defect insensitive propagating character and
Talbot effect.


title: Forgotten Motives: the Varieties of Scientific Experience

abstract:
  Personal recollections about Alexandre Grothendieck and early days of his
theory of motives


title:
Uncertainty Quantification for Linear Hyperbolic Equations with
  Stochastic Process or Random Field Coefficients

abstract:
  In this paper hyperbolic partial differential equations with random
coefficients are discussed. Such random partial differential equations appear
for instance in traffic flow problems as well as in many physical processes in
random media. Two types of models are presented: The first has a time-dependent
coefficient modeled by the Ornstein--Uhlenbeck process. The second has a random
field coefficient with a given covariance in space. For the former a formula
for the exact solution in terms of moments is derived. In both cases stable
numerical schemes are introduced to solve these random partial differential
equations. Simulation results including convergence studies conclude the
theoretical findings.


title:
Existence of Invariant Measures of Stochastic Systems with Delay in the
  Highest Order Partial Derivatives

abstract:
  In this note, we shall consider the existence of invariant measures for a
class of infinite dimensional stochastic functional differential equations with
delay whose driving semigroup is eventually norm continuous. The results
obtained are applied to stochastic heat equations with distributed delays which
appear in such terms having the highest order partial derivatives. In the
systems, the associated driving semigroups are generally non eventually
compact.


title: Big Bang, Blowup, and Modular Curves: Algebraic Geometry in Cosmology

abstract:
  We introduce some algebraic geometric models in cosmology related to the
"boundaries" of space-time: Big Bang, Mixmaster Universe, Penrose's crossovers
between aeons. We suggest to model the kinematics of Big Bang using the
algebraic geometric (or analytic) blow up of a point $x$. This creates a
boundary which consists of the projective space of tangent directions to $x$
and possibly of the light cone of $x$. We argue that time on the boundary
undergoes the Wick rotation and becomes purely imaginary. The Mixmaster
(Bianchi IX) model of the early history of the universe is neatly explained in
this picture by postulating that the reverse Wick rotation follows a hyperbolic
geodesic connecting imaginary time axis to the real one. Penrose's idea to see
the Big Bang as a sign of crossover from "the end of previous aeon" of the
expanding and cooling Universe to the "beginning of the next aeon" is
interpreted as an identification of a natural boundary of Minkowski space at
infinity with the Big Bang boundary.


title: Diffuse scattering in ice Ih

abstract:
  Single crystals of ice Ih, extracted from the subglacial Lake Vostok
accretion ice layer (3621 m depth) were investigated by means of diffuse x-ray
scattering and inelastic x-ray scattering. The diffuse scattering was
identified as mainly inelastic and rationalized in the frame of ab initio
calculations for the ordered ice XI approximant. Together with Monte-Carlo
modelling our data allowed reconsidering previously available neutron diffuse
scattering data of heavy ice as the sum of thermal diffuse scattering and
static disorder contribution.


title:
Morphology-driven electrical and optical properties in graded
  hierarchical transparent conducting Al:ZnO

abstract:
  Graded Al-doped ZnO layers, constituted by a mesoporous forest like system
evolving into a compact transparent conductor, were synthesized by Pulsed Laser
Deposition with different morphology to study the correlation with functional
properties. Morphology was monitored by measuring the resulting surface
roughness and its effects on electrical conductivity (especially carrier
mobility, which significantly decreases with increasing roughness) allow to
discuss the limitations in conduction mechanisms. Significant changes in light
scattering capability due to variations in morphology are also investigated and
discussed to study the correlation between morphology and functional
properties.


title: Probing cosmic opacity at high redshifts with gamma-ray bursts

abstract:
  Probing the evolution of the universe at high redshifts with standard candles
is a powerful way to discriminate dark energy models, where an open question
nowadays is whether this component is constant or evolves with time. One
possible source of ambiguity in this kind of analyses comes from cosmic
opacity, which can mimick a dark enery behaviour. However, most tests of cosmic
opacity have been restricted to the redshift range $z<2$. In this work, by
using luminosity distances of gamma-ray bursts (GRBs), {given the validity of
the Amati relation}, and the latest $H(z)$ data we determine constraints on the
cosmic opacity at high redshifts ($z>2$) for a flat $\Lambda$CDM model. A
possible degenerescence of the results with the adopted cosmological model is
also investigated by considering a flat XCDM model. The limits on cosmic
opacity in the redshift range $0<z<2$ are updated with type Ia supernovae (SNe
Ia) from the Union2.1 sample, where we added the most distant ($z=1.713$)
spectroscopically confirmed SNe Ia. From the analyses performed, we find that
both SNe Ia and GRBs samples are compatible with a transparent universe at
$1\sigma$ level and the results are independent of the dark energy equation of
state parameter $w$.


title: QED spectra in the path integral formalism

abstract:
  Relativistic Hamiltonians, derived from the path integrals, are known to
provide a simple and useful formalism for hadrons spectroscopy in QCD. The
accuracy of this approach is tested using the QED systems, and the calculated
spectrum is shown to reproduce exactly that of the Dirac hydrogen atom, while
the Breit-Fermi nonrelativistic expansion is obtained using Foldy-Wouthuizen
transformation. Calculated positronium spectrum, including spin-dependent
terms, coincides with the standard QED perturbation theory to the considered
order O(alpha^s).


title: Zeeman shift of an electron trapped near a surface

abstract:
  Boundary dependent corrections to the spin energy eigenvalues of an electron
in a weak magnetic field and confined by a harmonic trapping potential are
investigated. The electromagnetic field is quantized through a normal mode
expansion obeying the Maxwell boundary conditions at the material surface. We
couple the electron to this photon field and a classical magnetic field in the
Dirac equation, to which we apply the unitary Foldy-Wouthuysen transformation
in order to generate a non-relativistic approximation of the Hamiltonian to the
desired order. We obtain the Schr\"odinger eigenstates of an electron subject
to double confinement by a harmonic potential and a classical magnetic field,
and then use these within second-order perturbation theory to calculate the
spin energy shift that is attributable to the surface-modified quantized field.
We find that a pole at the eigenfrequency of a set of generalized Landau
transitions gives dominant oscillatory contributions to the energy shift in the
limit of tight harmonic confinement in a weak magnetic field, which also make
the energy shift preferable to the magnetic moment for a physically meaningful
interpretation.


title: Evidence for an external origin of heavy elements in hot DA white dwarfs

abstract:
  We present a series of systematic abundance measurements for 89 hydrogen
atmosphere (DA-type) white dwarfs with temperatures spanning 16000-77000K drawn
from the FUSE spectral archive. This is the largest study to date of white
dwarfs where radiative forces are significant, exceeding our earlier work,
based mainly on IUE and HST data, by a factor three. Using heavy element
blanketed non-LTE stellar atmosphere calculations, we have addressed the heavy
element abundance patterns making completely objective measurements of
abundance values and their error ranges using a \c{hi}2 fitting technique. We
are able to establish the broad range of abundances seen in a given temperature
range and establish the incidence of stars which appear, in the optical, to be
atmospherically devoid of any material other than H. We compare the observed
abundances to predictions of radiative levitation calculations, revealing
little agreement. We propose that the supply of heavy elements is accreted from
external sources rather than being intrinsic to the star. These elements are
then retained in the white dwarf atmospheres by radiative levitation, a model
that can explain both the diversity of measured abundances for stars of similar
temperature and gravity, including cases with apparently pure H envelopes, and
the presence of photospheric metals at temperatures where radiative levitation
is no longer effective.


title: Strong spin-phonon coupling in infrared and Raman spectra of SrMnO3

abstract:
  Infrared reflectivity spectra of cubic SrMnO$_{3}$ ceramics reveal 18 %
stiffening of the lowest-frequency phonon below the antiferromagnetic phase
transition occurring at T$_{N}$ = 233 K. Such a large temperature change of the
polar phonon frequency is extraordinary and we attribute it to an exceptionally
strong spin-phonon coupling in this material. This is consistent with our
prediction from first principles calculations. Moreover, polar phonons become
Raman active below T$_{N}$, although their activation is forbidden by symmetry
in $Pm\bar{3}m$ space group. This gives evidence that the cubic $Pm\bar{3}m$
symmetry is locally broken below T$_{N}$ due to a strong magnetoelectric
coupling. Multiphonon and multimagnon scattering is also observed in Raman
spectra. Microwave and THz permittivity is strongly influenced by hopping
electronic conductivity, which is caused by small non-stoichiometry of the
sample. Thermoelectric measurements show room-temperature concentration of free
carriers $n_{e}=$3.6 10$^{20}$ cm$^{-3}$ and the sample composition
Sr$^{2+}$Mn$_{0.98}^{4+}$Mn$_{0.02}^{3+}$O$_{2.99}^{2-}$. The conductivity
exhibits very unusual temperature behavior: THz conductivity increases on
cooling, while the static conductivity markedly decreases on cooling. We
attribute this to different conductivity of the ceramic grains and grain
boundaries.


title: Fully commutative elements in finite and affine Coxeter groups

abstract:
  An element of a Coxeter group $W$ is fully commutative if any two of its
reduced decompositions are related by a series of transpositions of adjacent
commuting generators. These elements were extensively studied by Stembridge, in
particular in the finite case. They index naturally a basis of the generalized
Temperley--Lieb algebra. In this work we deal with any finite or affine Coxeter
group $W$, and we give explicit descriptions of fully commutative elements.
Using our characterizations we then enumerate these elements according to their
Coxeter length, and find in particular that the corrresponding growth sequence
is ultimately periodic in each type. When the sequence is infinite, this
implies that the associated Temperley--Lieb algebra has linear growth.


title:
Planes of matrices of constant rank and globally generated vector
  bundles

abstract:
  We consider the problem of determining all pairs (c_1, c_2) of Chern classes
of rank 2 bundles that are cokernel of a skew-symmetric matrix of linear forms
in 3 variables, having constant rank 2c_1 and size 2c_1+2. We completely solve
the problem in the "stable" range, i.e. for pairs with c_1^2-4c_2<0, proving
that the additional condition c_2\le {{c_1+1}\choose 2} is necessary and
sufficient. For c_1^2-4c_2\ge 0, we prove that there exist globally generated
bundles, some even defining an embedding of P^2 in a Grassmannian, that cannot
correspond to a matrix of the above type. This extends previous work on c_1\le
3.


title:
Low-lying states in near-magic odd-odd nuclei and the effective
  interaction

abstract:
  The iterative quasi-particle-random-phase approximation (QRPA) method we
previously developed to accurately calculate properties of individual nuclear
states is extended so that it can be applied for nuclei with odd numbers of
neutrons and protons. The approach is based on the proton-neutron-QRPA (pnQRPA)
and uses an iterative non-hermitian Arnoldi diagonalization method where the
QRPA matrix does not have to be explicitly calculated and stored. The method is
used to calculate excitation energies of proton-neutron multiplets for several
nuclei. The influence of a pairing interaction in the $T=0$ channel is studied.


title: The Spatial Sensitivity Function of a Light Sensor

abstract:
  The Spatial Sensitivity Function (SSF) is used to quantify a detector's
sensitivity to a spatially-distributed input signal. By weighting the incoming
signal with the SSF and integrating, the overall scalar response of the
detector can be estimated. This project focuses on estimating the SSF of a
light intensity sensor consisting of a photodiode. This light sensor has been
used previously in the Knuth Cyberphysics Laboratory on a robotic arm that
performs its own experiments to locate a white circle in a dark field (Knuth et
al., 2007). To use the light sensor to learn about its surroundings, the
robot's inference software must be able to model and predict the light sensor's
response to a hypothesized stimulus. Previous models of the light sensor
treated it as a point sensor and ignored its spatial characteristics. Here we
propose a parametric approach where the SSF is described by a mixture of
Gaussians (MOG). By performing controlled calibration experiments with known
stimulus inputs, we used nested sampling to estimate the SSF of the light
sensor using an MOG model with the number of Gaussians ranging from one to
five. By comparing the evidence computed for each MOG model, we found that one
Gaussian is sufficient to describe the SSF to the accuracy we require. Future
work will involve incorporating this more accurate SSF into the Bayesian
machine learning software for the robotic system and studying how this detailed
information about the properties of the light sensor will improve robot's
ability to learn.


title:
Partial-Wave Analysis of Centrally Produced Two-Pseudoscalar Final
  States in pp Reactions at COMPASS

abstract:
  COMPASS is a fixed-target experiment at the CERN SPS which focused on
light-quark hadron spectroscopy during the data taking periods in 2008 and
2009. A world-leading data set was collected with a 190GeV/c hadron beam
impinging on a liquid hydrogen target in order to study, inter alia, the
central exclusive production of glueball candidates in the light-meson sector.
Especially the double-Pomeron exchange mechanism is well suited for the
production of mesons without valence quark content. We select centrally
produced systems with two pseudo-scalar mesons in the final state from the
COMPASS data set recorded with an incoming proton. The decay of this system is
decomposed in terms of partial waves, where particular attention is paid to the
inherent mathematical ambiguities of the amplitude analysis. Furthermore, we
show that simple parametrisations are able to describe the mass dependence of
the fit results with sensible Breit-Wigner parameters.


title:
A new low-cost meshfree method for two and three dimensional problems in
  elasticity

abstract:
  In this paper, we continue the development of the Direct Meshless Local
Petrov-Galerkin (DMLPG) method for elasto-static problems. This method is based
on the generalized moving least squares approximation. The computational
efficiency is the most significant advantage of the new method in comparison
with the original MLPG. Although, the "Petrov-Galerkin" strategy is used to
build the primary local weak forms, the role of trial space is ignored and
direct approximations for local weak forms and boundary conditions are
performed to construct the final stiffness matrix. In this modification the
numerical integrations are performed over polynomials instead of complicated
MLS shape functions. In this paper, DMLPG is applied for two and three
dimensional problems in elasticity. Some variations of the new method are
developed and their efficiencies are reported. Finally, we will conclude that
DMLPG can replace the original MLPG in many situations.


title:
Development of CMOS pixel sensors for tracking and vertexing in high
  energy physics experiments

abstract:
  CMOS pixel sensors (CPS) represent a novel technological approach to building
charged particle detectors. CMOS processes allow to integrate a sensing volume
and readout electronics in a single silicon die allowing to build sensors with
a small pixel pitch ($\sim 20 \mu m$) and low material budget ($\sim 0.2-0.3\%
X_0$) per layer. These characteristics make CPS an attractive option for
vertexing and tracking systems of high energy physics experiments. Moreover,
thanks to the mass production industrial CMOS processes used for the
manufacturing of CPS the fabrication construction cost can be significantly
reduced in comparison to more standard semiconductor technologies. However, the
attainable performance level of the CPS in terms of radiation hardness and
readout speed is mostly determined by the fabrication parameters of the CMOS
processes available on the market rather than by the CPS intrinsic potential.
  The permanent evolution of commercial CMOS processes towards smaller feature
sizes and high resistivity epitaxial layers leads to the better radiation
hardness and allows the implementation of accelerated readout circuits. The
TowerJazz $0.18 \mu m$ CMOS process being one of the most relevant examples
recently became of interest for several future detector projects. The most
imminent of these project is an upgrade of the Inner Tracking System (ITS) of
the ALICE detector at LHC. It will be followed by the Micro-Vertex Detector
(MVD) of the CBM experiment at FAIR. Other experiments like ILD consider CPS as
one of the viable options for flavour tagging and tracking sub-systems.


title:
A new concept for safeguarding and labeling of long-term stored waste
  and its place in the scope of existing tagging techniques

abstract:
  The idea of a novel labeling method is suggested for a new way of long-term
security identification, inventory tracking, prevention of falsification and
theft of waste casks, copper canisters, spent fuel containers, mercury
containers, waste packages and other items. The suggested concept is based on
the use of a unique combination of radioisotopes with different predictable
half life. As an option for applying the radioisotope tag to spent fuel
safeguarding it is suggested to use a mixture of {\alpha}-emitting isotopes,
such as 241Am etc., with materials that easily undergo {\alpha}-induced
reactions with emission of specific {\gamma}-lines. Thus, the existing problem
of the disposing of smoke detectors or other devices [1] which contain
radioisotopes can be addressed, indirectly solving an existing waste problem.
The results of the first pilot experiments with two general designs of storage
canisters, namely a steel container which corresponds to the one which is
commonly used for long-term storing of mercury in Europe and USA and a copper
canister, the one which is in applications for nuclear repositories, are
presented. As one of the options for a new labeling method it is proposed to
use a multidimensional bar code symbology and tungsten plate with ultrasound
techniques. It is shown that the new radioisotope label offers several
advantages in the scope of existing tagging techniques (overview is given) and
can be implemented even with low activity sources.


title: Generic lepton mass matrices and neutrino oscillations

abstract:
  Several intriguing aspects of neutrino oscillation phenomenology like the
origin of small neutrino masses, the absolute neutrino mass scale, the neutrino
mass hierarchy, i.e. normal or inverted and the nature of neutrinos, i.e. Dirac
or Majorana, etc. have been addressed from a general perspective. We show how
the fundamental considerations of unitary transformations, naturalness and
seesaw mechanism suffices to determine the texture structure of fermion Yukawa
couplings and discuss the significance of the effective mass in
0{\nu}{\beta}{\beta} decay for the texture structure of these couplings.


title:
A Characterization of Locally Testable Affine-Invariant Properties via
  Decomposition Theorems

abstract:
  Let $\mathcal{P}$ be a property of function $\mathbb{F}_p^n \to \{0,1\}$ for
a fixed prime $p$. An algorithm is called a tester for $\mathcal{P}$ if, given
a query access to the input function $f$, with high probability, it accepts
when $f$ satisfies $\mathcal{P}$ and rejects when $f$ is "far" from satisfying
$\mathcal{P}$. In this paper, we give a characterization of affine-invariant
properties that are (two-sided error) testable with a constant number of
queries. The characterization is stated in terms of decomposition theorems,
which roughly claim that any function can be decomposed into a structured part
that is a function of a constant number of polynomials, and a pseudo-random
part whose Gowers norm is small. We first give an algorithm that tests whether
the structured part of the input function has a specific form. Then we show
that an affine-invariant property is testable with a constant number of queries
if and only if it can be reduced to the problem of testing whether the
structured part of the input function is close to one of a constant number of
candidates.


title:
Search for W' to tb decays in the lepton + jets final state in pp
  collisions at sqrt(s) = 8 TeV

abstract:
  Results are presented from a search for the production of a heavy gauge boson
W' decaying into a top and a bottom quark, using a data set collected by the
CMS experiment at sqrt(s) = 8 TeV and corresponding to an integrated luminosity
of 19.5 inverse femtobarns. Various models of W'-boson production are studied
by allowing for an arbitrary combination of left- and right-handed couplings.
The analysis is based on the detection of events with a lepton (e, mu), jets,
and missing transverse energy in the final state. No evidence for W'-boson
production is found and 95% confidence level upper limits on the production
cross section times branching fraction are obtained. For W' bosons with purely
right-handed couplings, and for those with left-handed couplings assuming no
interference effects, the observed 95% confidence level limit is M(W') > 2.05
TeV. For W' bosons with purely left-handed couplings, including interference
effects, the observed 95% confidence level limit is M(W') > 1.84 TeV. The
results presented in this paper are the most stringent limits published to
date.


title: Riesz and frame systems generated by unitary actions of discrete groups

abstract:
  We characterize orthonormal bases, Riesz bases and frames which arise from
the action of a countable discrete group $\Gamma$ on a single element $\psi$ of
a given Hilbert space $\mathcal{H}$. As $\Gamma$ might not be abelian, this is
done in terms of a bracket map taking values in the $L^1$-space associated to
the group von Neumann algebra of $\Gamma$. Our result generalizes recent work
for LCA groups. In many cases, the bracket map can be computed in terms of a
noncommutative form of the Zak transform.


title:
Multiplicative relations between coefficients of logarithmic derivatives
  of $\mathbb{F}_q$-linear functions and applications

abstract:
  We prove some interesting multiplicative relations which hold between the
coefficients of the logarithmic derivatives obtained in a few simple ways from
$\mathbb{F}_q$-linear formal power series. Since the logarithmic derivatives
connect power sums to elementary symmetric functions via the Newton identities,
we establish, as applications, new identities between important quantities of
function field arithmetic, such as the Bernoulli-Carlitz fractions and power
sums as well as their multi-variable generalizations. Resulting understanding
of their factorizations has arithmetic significance, as well as applications to
function field zeta and multizeta values evaluations and relations between
them. Using specialization/generalization arguments, we provide much more
general identities on linear forms providing a switch between power sums for
positive and negative powers.


title: Orbital magnetization in dilute ferromagnetic semiconductors

abstract:
  The relationship between the modern and classical Landau's approach to
carrier orbital magnetization is studied theoretically within the envelope
function approximation, taking ferromagnetic (Ga,Mn)As as an example. It is
shown that while the evaluation of hole magnetization within the modern theory
does not require information on the band structure in a magnetic field, the
number of basis wave functions must be much larger than in the Landau approach
to achieve the same quantitative accuracy. A numerically efficient method is
proposed, which takes advantages of these two theoretical schemes. The computed
magnitude of orbital magnetization is in accord with experimental values
obtained by x-ray magnetic circular dichroism in (III,Mn)V compounds. The
direct effect of the magnetic field on the hole spectrum is studied too, and
employed to interpret a dependence of the Coulomb blockade maxima on the
magnetic field in a single electron transistor with a (Ga,Mn)As gate.


title: Controlling inertial focussing using rotational motion

abstract:
  In inertial microfluidics lift forces cause a particle to migrate across
streamlines to specific positions in the cross section of a microchannel. We
control the rotational motion of a particle and demonstrate that this allows to
manipulate the lift-force profile and thereby the particle's equilibrium
positions. We perform two-dimensional simulation studies using the method of
multi-particle collision dynamics. Particles with unconstrained rotational
motion occupy stable equilibrium positions in both halfs of the channel while
the center is unstable. When an external torque is applied to the particle, two
equilibrium positions annihilate by passing a saddle-node bifurcation and only
one stable fixpoint remains so that all particles move to one side of the
channel. In contrast, non-rotating particles accumulate in the center and are
pushed into one half of the channel when the angular velocity is fixed to a
non-zero value.


title:
{\kappa} state solutions for the fermionic massive spin-1/2 particles
  interacting with double ring-shaped Kratzer and oscillator potentials

abstract:
  In recent years, an extensive survey on various wave equations of
relativistic quantum mechanics with different types of potential interactions
has been a line of great interest. In this regime, special attention has been
given to the Dirac equation because the spin-1/2 fermions represent the most
frequent building blocks of the molecules and atoms. Motivated by the
considerable interest in this equation and its relativistic symmetries (spin
and pseudospin) in the presence of solvable potential model, we attempt to
obtain the relativistic bound states solution of the Dirac equation with double
ring-shaped Kratzer and oscillator potentials under the condition of spin and
pseudospin symmetries. The solutions are reported for arbitrary quantum number
in a compact form. the analytic bound state energy eigenvalues and the
associated upper- and lower-spinor components of two Dirac particles have been
found. Several typical numerical results of the relativistic eigenenergies have
also been presented. We found that the existence or absence of the ring shaped
potential potential has strong effects on the eigenstates of the Kratzer and
oscillator particles with a wide band spectrum except for the
pseudospin-oscillator particles where there exist a narrow band gap.


title:
$\alpha$-decay calculations of heavy nuclei using an effective Skyrme
  interaction

abstract:
  Background: For nuclei heavier than $^{208}$Pb $\alpha$ decay is a dominating
decay mode, and in the search of new superheavy elements one often observes
chains of $\alpha$ decays. Purpose: Explore and test microscopic descriptions
of $\alpha$ decay based on theories with effective nuclear interactions.
Methods: The nuclear ground states are calculated with the
Hartree-Fock-Bogoliubov (HFB) method using the Skyrme interaction. Microscopic
$\alpha$-decay formation amplitudes are calculated from the HFB wave functions,
and the $R$-matrix formalism is utilized to obtain decay probabilities.
Results: Using a large harmonic-oscillator basis we obtain converged
$\alpha$-decay widths. A comparison with experiment including all spherical
even-even $\alpha$ emitting nuclei shows that the model consistently predicts
too small formation amplitudes while relative values are in good agreement with
experiment. Conclusions: The method was found to be numerically practical even
with a large basis size. The comparison of formation amplitudes suggests that
the pairing type correlations included in the HFB approach cannot produce
sufficient $\alpha$-particle clustering.


title: Discrete tomography: Magic numbers for $N$-fold symmetry

abstract:
  We consider the problem of distinguishing convex subsets of $n$-cyclotomic
model sets $\varLambda$ by (discrete parallel) X-rays in prescribed
$\varLambda$-directions. In this context, a `magic number' $m_{\varLambda}$ has
the property that any two convex subsets of $\varLambda$ can be distinguished
by their X-rays in any set of $m_{\varLambda}$ prescribed
$\varLambda$-directions. Recent calculations suggest that (with one exception
in the case $n=4$) the least possible magic number for $n$-cyclotomic model
sets might just be $N+1$, where $N=\operatorname{lcm}(n,2)$.


title: A SAT Attack on the Erdos Discrepancy Conjecture

abstract:
  In 1930s Paul Erdos conjectured that for any positive integer C in any
infinite +1 -1 sequence (x_n) there exists a subsequence x_d, x_{2d}, ... ,
x_{kd} for some positive integers k and d, such that |x_d + x_{2d} + ... +
x_{kd}|> C. The conjecture has been referred to as one of the major open
problems in combinatorial number theory and discrepancy theory. For the
particular case of C=1 a human proof of the conjecture exists; for C=2 a
bespoke computer program had generated sequences of length 1124 having
discrepancy 2, but the status of the conjecture remained open even for such a
small bound. We show that by encoding the problem into Boolean satisfiability
and applying the state of the art SAT solvers, one can obtain a sequence of
length 1160 with discrepancy 2 and a proof of the Erdos discrepancy conjecture
for C=2, claiming that no sequence of length 1161 and discrepancy 2 exists. We
also present our partial results for the case of C=3.


title:
Relativity, the Special Theory, explained to Children (from 7 to 107
  years old)

abstract:
  The author thinks that the main ideas or Relativity Theory can be explained
to children (around the age of 15 or 16) without complicated calculations, by
using very simple arguments of affine geometry. The proposed approach is
presented as a conversation between the author and one of his grand-children.
Limited here to the Special Theory, it will be extended to the General Theory
elsewhere, as sketched in conclusion.


title: Alpha-particle formation and decay rates from Skyrme-HFB wave functions

abstract:
  $\alpha$ decay is treated microscopically, where the unstable mother nucleus
and residual daughter nucleus are described using HFB wave functions, obtained
with the Skyrme effective interaction. From these wave functions the amplitude
for forming $\alpha$ particles in the mother nucleus is computed. Two different
Skyrme parametrizations with different pairing properties are compared, and we
find good agreement with experiment for relative decay rates in both cases. The
absolute values of the decay rates are under-estimated.


title:
Analyzing Peer Selection Policies for BitTorrent Multimedia On-Demand
  Streaming Systems in Internet

abstract:
  The adaptation of the BitTorrent protocol to multimedia on-demand streaming
systems essentially lies on the modification of its two core algorithms, namely
the piece and the peer selection policies, respectively. Much more attention
has though been given to the piece selection policy. Within this context, this
article proposes three novel peer selection policies for the design of
BitTorrent-like protocols targeted at that type of systems: Select Balanced
Neighbour Policy (SBNP), Select Regular Neighbour Policy (SRNP), and Select
Optimistic Neighbour Policy (SONP). These proposals are validated through a
competitive analysis based on simulations which encompass a variety of
multimedia scenarios, defined in function of important characterization
parameters such as content type, content size, and client interactivity
profile. Service time, number of clients served and efficiency retrieving
coefficient are the performance metrics assessed in the analysis. The final
results mainly show that the novel proposals constitute scalable solutions that
may be considered for real project designs. Lastly, future work is included in
the conclusion of this paper.


title: Handwritten Character Recognition In Malayalam Scripts- A Review

abstract:
  Handwritten character recognition is one of the most challenging and ongoing
areas of research in the field of pattern recognition. HCR research is matured
for foreign languages like Chinese and Japanese but the problem is much more
complex for Indian languages. The problem becomes even more complicated for
South Indian languages due to its large character set and the presence of
vowels modifiers and compound characters. This paper provides an overview of
important contributions and advances in offline as well as online handwritten
character recognition of Malayalam scripts.


title:
Nanopatterning by Laser Interference Lithography: Applications to
  Optical Devices

abstract:
  A systematic review, covering fabrication of nanoscale patterns by laser
interference lithography (LIL) and their applications for optical devices are
provided. LIL is a patterning method with simple, quick process over a large
area without using a mask. LIL is a powerful technique for the definition of
large-area, nanometer-scale, periodically patterned structures. Patterns are
recorded in a light-sensitive medium that responds nonlinearly to the intensity
distribution associated with the interference of two or more coherent beams of
light. The photoresist patterns produced with LIL are the platform for further
fabrication of nanostructures and growth of functional materials which are the
building blocks for devices. Demonstration of optical and photonic devices by
LIL is reviewed such as directed nano photonics and surface plasmon resonance
(SPR) or large area membrane reflectors and anti-reflectors. Perspective on
future directions for LIL and emerging applications in other fields are
presented.


title:
Surfaces Representation with Sharp Features Using Sqrt(3) and Loop
  Subdivision Schemes

abstract:
  This paper presents a hybrid algorithm that combines features form both
Sqrt(3) and Loop Subdivision schemes. The algorithm aims at preserving sharp
features and trim regions, during the surfaces subdivision, using a set of
rules. The implementation is nontrivial due to the computational, topological,
and smoothness constraints, which should be satisfied by the underlying
surface. The fundamental innovation, in this research work, is the ability to
preserve sharp features anywhere on a surface. In addition, the resulting
representation remains within the multiresolution subdivision framework.
Preserving the original representation has a core advantage that all the
applicable operations to the multiresolution subdivision surfaces can
subsequently be applied to the edited model. Experimental results, including
surfaces coarsening and smoothing, were performed using the proposed algorithm
for validation purposes, and the results revealed that the proposed algorithm
outperforms the other recent state of the art algorithms.


title:
A new equivalence of Stefan's problems for the Time-Fractional-Diffusion
  Equation

abstract:
  A fractional Stefan problem with a boundary convective condition is solved,
where the fractional derivative of order $ \alpha \in (0,1) $ is taken in the
Caputo sense. Then an equivalence with other two fractional Stefan problems
(the first one with a constant condition on $ x = 0 $ and the second with a
flux condition)is proved and the convergence to the classical solutions is
analyzed when $ \alpha \nearrow 1$ recovering the heat equation with its
respective Stefan condition.


title:
Kramers escape rate in overdamped systems with the power-law
  distribution

abstract:
  Kramers escape rate in the overdamped systems with the power-law distribution
is studied. By using the mean first passage time, we derive the escape rate for
the power-law distribution and obtain the Kramers' infinite barrier escape rate
in this case. It is shown that the escape rate for the power-law distribution
extends the Kramers' overdamped result to the relatively low barrier.
Furthermore, we apply the escape rate for the power-law distribution to the
unfolding of titin and show a better agreement with the experimental rate than
the traditional escape rate.


title:
On the Schr\"odinger equations with isotropic and anisotropic
  fourth-order dispersion

abstract:
  This paper deals with the Cauchy problem associated to the nonlinear
fourth-order Schr\"odinger equation with isotropic and anisotropic mixed
dispersion. This model is given by the equation $i\partial _{t}u+\epsilon
\Delta u+\delta A u+\lambda|u|^\alpha u=0,$ $x\in \mathbb{R}^{n},$ $t\in
\mathbb{R},$ where $A$ represents either the operator $\Delta^2$ (isotropic
dispersion) or $\sum_{i=1}^d\partial_{x_ix_ix_ix_i},\ 1\leq d<n$ (anisotropic
dispersion), and $\alpha, \epsilon, \lambda$ are given real parameters. We
obtain local and global well-posedness results in spaces of initial data with
low regularity, such as weak-$L^p$ spaces. Our analysis also includes the
biharmonic and anisotropic biharmonic equation $(\epsilon=0)$ for which, the
existence of self-similar solutions is obtained as consequence of his scaling
invariance. In a second part, we investigate the vanishing second order
dispersion limit in the framework of weak-$L^p$ spaces. We also analyze the
convergence of the solutions for the nonlinear fourth-order Schr\"odinger
equation $i\partial _{t}u+\epsilon \Delta u+\delta \Delta^2 u+\lambda|u|^\alpha
u=0$, as $\epsilon$ goes to zero, in $H^2$-norm, to the solutions of the
corresponding biharmonic equation $i\partial _{t}u+\delta \Delta^2
u+\lambda|u|^\alpha u=0$.


title: Dynamic control of modern, network-based epidemic models

abstract:
  In this paper we make the first steps to bridge the gap between classic
control theory and modern, network-based epidemic models. In particular, we
apply nonlinear model predictive control (NMPC) to a pairwise ODE model which
we use to model a susceptible-infectious-susceptible (SIS) epidemic on
non-trivial contact structures. While classic control of epidemics concentrates
on aspects such as vaccination, quarantine and fast diagnosis, our novel setup
allows us to deliver control by altering the contact network within the
population. Moreover, the ideal outcome of control is to eradicate the disease
while keeping the network well connected. The paper gives a thorough and
detailed numerical investigation of the impact and interaction of system and
control parameters on the controllability of the system. The analysis reveals,
that for certain set parameters it is possible to identify critical control
bounds above which the system is controllable. We foresee, that our approach
can be extended to even more realistic or simulation-based models with the aim
to apply these to real-world situations.


title: Rydberg atoms in hollow-core photonic crystal fibres

abstract:
  The exceptionally large polarisability of highly excited Rydberg atoms (six
orders of magnitude higher than ground-state atoms) makes them of great
interest in fields such as quantum optics, quantum computing, quantum
simulation and metrology. If however they are to be used routinely in
applications, a major requirement is their integration into technically
feasible, miniaturised devices. Here we show that a Rydberg medium based on
room temperature caesium vapour can be confined in broadband-guiding
kagome-style hollow-core photonic crystal fibres. Three-photon spectroscopy
performed on a caesium-filled fibre detects Rydberg states up to a principal
quantum number of n = 40. Besides small energy level shifts we observe narrow
lines confirming the coherence of the Rydberg excitation. Using different
Rydberg states and core diameters we study the influence of confinement within
the fibre core after different exposure times. Understanding these effects is
essential for the successful future development of novel applications based on
integrated room temperature Rydberg systems.


title:
Affective and cognitive prefrontal cortex projections to the lateral
  habenula in humans

abstract:
  Anterior insula (AI) and dACC are known to process information about pain,
loss, adversities, bad, harmful or suboptimal choices and consequences that
threaten survival or well-being. Pain and loss activate also pregenual ACC
(pgACC), linked to sad thoughts, hurt and regrets. The lateral habenula (LHb)
is stimulated by predicted and received pain, discomfort, aversive outcome,
loss. Its chronic stimulation makes us feel worse/low and gradually stops us
choosing and moving for suboptimal, hurtful or punished choices, by direct and
indirect (via RMTg) inhibition of DRN and VTA/SNc. Response selectivity of LHb
neurons suggests their cortical input from affective and cognitive evaluative
regions that make expectations about bad or suboptimal outcomes. Based on these
facts I predicted direct corticohabenular projections from the dACC, pgACC and
AI, as part of the adversity processing circuit that learns to avoid bad
outcomes by suppressing dopamine and serotonin signal. Using DTI I found dACC,
pgACC, AI, adjacent caudolateral and lateral OFC projections to LHb. I
predicted no corticohabenular projections from the reward processing regions:
medial OFC and vACC because both respond most strongly to good, high value
stimuli and outcomes, inducing serotonin and dopamine release respectively.
This lack of LHb projections was confirmed for vACC and likely for mOFC. The
surprising findings were the corticohabenular projections from the cognitive
prefrontal cortex regions, known for flexible reasoning, planning and combining
whatever information are relevant for reaching current goals. I propose that
prefrontohabenular projections provide a teaching signal for value-based choice
behaviour, to learn to deselect, avoid or inhibit the potentially harmful, low
valued or wrong choices, goals, strategies, predictions, models and ways of
doing things, to prevent bad or suboptimal consequences.


title:
Sensitivity of a superconducting nanowire detector for single ions at
  low energy

abstract:
  We report on the characterization of a superconducting nanowire detector for
ions at low kinetic energies. We measure the absolute single particle detection
efficiency $\eta$ and trace its increase with energy up to $\eta = 100$ %. We
discuss the influence of noble gas adsorbates on the cryogenic surface and
analyze their relevance for the detection of slow massive particles. We apply a
recent model for the hot spot formation to the incidence of atomic ions at
energies between 0.2-1 keV. We suggest how the differences observed for photons
and atoms or molecules can be related to the surface condition of the detector
and we propose that the restoration of proper surface conditions may open a new
avenue to SSPD-based optical spectroscopy on molecules and nanoparticles.


title: Multi-scale Representation of High Frequency Market Liquidity

abstract:
  We introduce an event based framework of directional changes and overshoots
to map continuous financial data into the so-called Intrinsic Network - a state
based discretisation of intrinsically dissected time series. Defining a method
for state contraction of Intrinsic Network, we show that it has a consistent
hierarchical structure that allows for multi-scale analysis of financial data.
We define an information theoretic measurement termed Liquidity that
characterises the unlikeliness of price trajectories and argue that the new
metric has the ability to detect and predict stress in financial markets. We
show empirical examples within the Foreign Exchange market where the new
measure not only quantifies liquidity but also acts as an early warning signal.


title:
Stationarity of Stochastic Linear Equations with Additive Noise and
  Delays in the Unbounded Drift Terms

abstract:
  This paper continues the study of [11, 13] for stationary solutions of
stochastic linear retarded functional differential equations with the emphasis
on delays which appear in those terms including spatial partial derivatives. As
a consequence, the associated stochastic equations have unbounded operators
acting on the discrete or distributed delayed terms, while the operator acting
on the instantaneous term generates a strongly continuous semigroup. We present
conditions on the delay systems to obtain a unique stationary solution by
combining spectrum analysis of unbounded operators and stochastic calculus. A
few instructive cases are analyzed in detail to clarify the underlying
complexity in the study of systems with unbounded delayed operators.


title: Structural study of alfa-Bi2O3 under pressure

abstract:
  An experimental and theoretical study of the structural properties of
monoclinic bismuth oxide (alfa-Bi2O3) under high pressures is here reported.
Both synthetic and mineral bismite powder samples have been compressed up to 45
GPa and their equations of state have been determined with angle-dispersive
x-ray diffraction measurements. Experimental results have been also compared to
theoretical calculations which suggest the possibility of several phase
transitions below 10 GPa. However, experiments reveal only a pressure-induced
amorphisation between 15 and 25 GPa, depending on sample quality and deviatoric
stresses. The amorphous phase has been followed up to 45 GPa and its nature
discussed.


title: Probing atomic environments in alloys by electron spectroscopy

abstract:
  In alloys exhibiting substitutional disorder, the variety of atomic
environments manifests itself as a `disorder broadening' in their core level
binding energy spectra. Disorder broadening can be measured experimentally, and
in principle can be used to deduce information about specific atomic
environments within a sample. However, progress in this endeavor is hampered by
the lack of a model for this phenomenon which can treat complex systems. In
this work we describe such a model. The model is used to elucidate the
relationship between charge transfer, atomic environment, and disorder
broadening in complex systems, with a focus on the problem of characterizing
the interface quality of CuNi multilayers. We also validate the model against
the results of ab initio electronic structure calculations. Several
counterintuitive aspects of the disorder broadening phenomenon are uncovered,
an understanding of which is essential for the correct interpretation of
experimental results. For instance, it is shown that systems with inhomogeneous
concentration profiles can exhibit disorder broadenings significantly larger
than random alloys. Furthermore in some systems a `disorder narrowing' is even
possible.


title: Dynamical properties of $k$-free lattice points

abstract:
  We revisit the visible points of a lattice in Euclidean $n$-space together
with their generalisations, the $k$th-power-free points of a lattice, and study
the corresponding dynamical system that arises via the closure of the lattice
translation orbit. Our analysis extends previous results obtained by Sarnak and
by Cellarosi and Sinai for the special case of square-free integers and sheds
new light on previous joint work with Peter Pleasants.


title:
A uniform model for Kirillov-Reshetikhin crystals II. Alcove model, path
  model, and P=X

abstract:
  We establish the equality of the specialization $P_\lambda(x;q,0)$ of the
Macdonald polynomial at $t=0$ with the graded character $X_\lambda(x;q)$ of a
tensor product of "single-column" Kirillov-Reshetikhin (KR) modules for
untwisted affine Lie algebras. This is achieved by constructing two uniform
combinatorial models for the crystals associated with the mentioned tensor
products: the quantum alcove model (which is naturally associated to Macdonald
polynomials), and the quantum Lakshmibai-Seshadri path model. We provide an
explicit affine crystal isomorphism between the two models, and realize the
energy function in both models. In particular, this gives the first proof of
the positivity of the $t = 0$ limit of the symmetric Macdonald polynomial in
the untwisted and non-simply-laced cases, when it is expressed as a linear
combination of the irreducible characters for a finite-dimensional simple Lie
subalgebra, as well as a representation-theoretic meaning of the coefficients
in this expression in terms of degree functions.


title:
Virtual Backbone Trees for Most Minimal Energy Consumption and
  Increasing Network Lifetime In WSNs

abstract:
  Virtual backbone trees have been used for efficient communication between
sink node and any other node in the deployed area. But all the proposed virtual
backbone trees are not fully energy efficient and EVBTs have few flaws
associated with them. In this paper two such virtual backbones are proposed.
The motive behind the first algorithm, Most Minimal Energy Virtual Backbone
Tree (MMEVBT), is to minimise the energy consumption when packets are
transmitted between sink and a target sensor node. The energy consumption is
most minimal and optimal and it is shown why it always has minimal energy
consumption during any transfer of packet between every node with the sink
node. For every node, route path with most minimal energy consumption is
identified and a new tree node is elected only when a better minimal energy
consumption route is identified for a node to communicate with the sink and
vice versa. By moving sink periodically it is ensured the battery of the nodes
near sink is not completely drained out. Another backbone construction
algorithm is proposed which maximises the network lifetime by increasing the
lifetime of all tree nodes. Simulations are done in NS2 to practically test the
algorithms and the results are discussed in detail.


title: Gibbs-Jaynes Entropy Versus Relative Entropy

abstract:
  The maximum entropy formalism developed by Jaynes determines the relevant
ensemble in nonequilibrium statistical mechanics by maximising the entropy
functional subject to the constraints imposed by the available information. We
present an alternative derivation of the relevant ensemble based on the
Kullback-Leibler divergence from equilibrium. If the equilibrium ensemble is
already known, then calculation of the relevant ensemble is considerably
simplified. The constraints must be chosen with care in order to avoid
contradictions between the two alternative derivations. The relative entropy
functional measures how much a distribution departs from equilibrium.
Therefore, it provides a distinct approach to the calculation of statistical
ensembles that might be applicable to situations in which the formalism
presented by Jaynes performs poorly (such as non-ergodic dynamical systems).


title:
Humanitarian Algorithms : A Codified Key Safety Switch Protocol for
  Lethal Autonomy

abstract:
  With the deployment of lethal autonomous weapons, there is the requirement
that any such platform complies with the precepts of International Humanitarian
Law. Humanitarian Algorithms[9: p. 9] ensure that lethal autonomous weapon
systems perform military/security operations, within the confines of
International Humanitarian Law. Unlike other existing techniques of regulating
lethal autonomy this scheme advocates for an approach that enables Machine
Learning. Lethal autonomous weapons must be equipped with appropriate fail-safe
mechanisms that locks them if they malfunction.


title: Bulk behaviour of Schur-Hadamard products of symmetric random matrices

abstract:
  We develop a general method for establishing the existence of the Limiting
Spectral Distributions (LSD) of Schur-Hadamard products of independent
symmetric patterned random matrices. We apply this method to show that the LSDs
of Schur-Hadamard products of some common patterned matrices exist and identify
the limits. In particular, the Schur-Hadamard product of independent Toeplitz
and Hankel matrices has the semi-circular LSD. We also prove an invariance
theorem that may be used to find the LSD in many examples.


title: A geometrically bounding hyperbolic link complement

abstract:
  A finite-volume hyperbolic 3-manifold geometrically bounds if it is the
geodesic boundary of a finite-volume hyperbolic 4-manifold. We construct here
an example of non-compact, finite-volume hyperbolic 3-manifold that
geometrically bounds. The 3-manifold is the complement of a link with eight
components, and its volume is roughly equal to 29.311.


title:
Approximative Tests for the Equality of Two Cumulative Incidence
  Functions of a Competing Risk

abstract:
  In the context of the widely used competing risks set-up we discuss different
inference procedures for testing equality of two cumulative incidence
functions, where the data may be subject to independent right-censoring or
left-truncation. To this end we compare two-sample Kolmogorov-Smirnov- and
Cramer-von Mises-type test statistics. Since, in general, their corresponding
asymptotic limit distributions depend on unknown quantities, we utilize wild
bootstrap resampling as well as approximation techniques to construct adequate
test decisions. Here the latter procedures are motivated from testing
procedures for heteroscedastic factorial designs but have not yet been proposed
in the survival context. A simulation study shows the performance of all
considered tests under various settings and finally a real data example about
bloodstream infection during neutropenia is used to illustrate their
application.


title:
Room temperature single-photon detectors for high bit rate quantum key
  distribution

abstract:
  We report room temperature operation of telecom wavelength single-photon
detectors for high bit rate quantum key distribution (QKD). Room temperature
operation is achieved using InGaAs avalanche photodiodes integrated with
electronics based on the self-differencing technique that increases avalanche
discrimination sensitivity. Despite using room temperature detectors, we
demonstrate QKD with record secure bit rates over a range of fiber lengths
(e.g. 1.26 Mbit/s over 50 km). Furthermore, our results indicate that operating
the detectors at room temperature increases the secure bit rate for short
distances.


title:
Oxygen diffusion and reactivity at low temperature on bare amorphous
  olivine-type silicate

abstract:
  The mobility of O atoms at very low temperatures is not generally taken into
account, despite O diffusion would add to a series of processes leading to the
observed rich molecular diversity in space. We present a study of the mobility
and reactivity of O atoms on an amorphous silicate surface. Our results are in
the form of RAIRS and temperature-programmed desorption spectra of O2 and O3
produced via two pathways: O + O and O2 + O, investigated in a submonolayer
regime and in the range of temperature between 6.5 and 30 K. All the
experiments show that ozone is formed efficiently on silicate at any surface
temperature between 6.5 and 30 K. The derived upper limit for the activation
barriers of O + O and O2 + O reactions is 150 K/kb. Ozone formation at low
temperatures indicates that fast diffusion of O atoms is at play even at 6.5 K.
Through a series of rate equations included in our model, we also address the
reaction mechanisms and show that neither the Eley Rideal nor the Hot atom
mechanisms alone can explain the experimental values. The rate of diffusion of
O atoms, based on modeling results, is much higher than the one generally
expected, and the diffusive process proceeds via the Langmuir-Hinshelwood
mechanism enhanced by tunnelling. In fact, quantum effects turn out to be a key
factor that cannot be neglected in our simulations. Astrophysically, efficient
O3 formation on interstellar dust grains would imply the presence of huge
reservoirs of oxygen atoms. Since O3 is a reservoir of elementary oxygen, and
also of OH via its hydrogenation, it could explain the observed concomitance of
CO2 and H2O in the ices.


title: Inner derivations of exceptional Lie algebras in prime characteristic

abstract:
  It is well-known that every derivation of a semisimple Lie algebra $L$ over
an algebraically closed field $F$ with characteristic zero is inner. The aim of
this paper is to show what happens if the characteristic of $F$ is prime with
$L$ an exceptional Lie algebra. We prove that if $L$ is a Chevalley Lie algebra
of type $\{G_2,F_4,E_6,E_7,E_8\}$ over a field of characteristic $p$ then the
derivations of $L$ are inner except in the cases $G_2$ with $p=2$, $E_6$ with
$p=3$ and $E_7$ with $p=2$.


title:
Challenging Adiabatic Time-dependent Density Functional Theory with a
  Hubbard Dimer: The Case of Time-Resolved Long-Range Charge Transfer

abstract:
  We explore an asymmetric two-fermion Hubbard dimer to test the accuracy of
the adiabatic approximation of time-dependent density functional theory in
modelling time-resolved charge transfer. We show that the model shares
essential features of a ground state long-range molecule in real-space, and by
applying a resonant field we show that the model also reproduces essential
traits of the CT dynamics. The simplicity of the model allows us to propagate
with an "adiabatically-exact" approximation, i.e. one that uses the exact
ground-state exchange-correlation functional, and compare with the exact
propagation. This allows us to study the impact of the time-dependent
charge-transfer step feature in the exact correlation potential of real
molecules on the resulting dynamics. Tuning the parameters of the dimer allows
a study both of charge-transfer between open-shell fragments and between
closed-shell fragments. We find that the adiabatically-exact functional is
unable to properly transfer charge, even in situations where the
adiabatically-exact resonance frequency is remarkably close to the exact
resonance, and we analyze why.


title:
Partially dualized Hopf algebras have equivalent Yetter-Drinfel'd
  modules

abstract:
  Given a Hopf algebra $H$ and a projection $H\to A$ to a Hopf subalgebra, we
construct a Hopf algebra $r(H)$, called the partial dualization of $H$, with a
projection to the Hopf algebra dual to $A$. This construction provides powerful
techniques in the general setting of braided monoidal categories. The
construction comprises in particular the reflections of generalized quantum
groups, arxiv:1111.4673 . We prove a braided equivalence between the
Yetter-Drinfel'd modules over a Hopf algebra and its partial dualization.


title:
Angle-resolved photoemission spectroscopy study of
  HgBa$_{2}$CuO$_{4+\delta}$

abstract:
  HgBa$_{2}$CuO$_{4+\delta}$ (Hg1201) has been shown to be a model cuprate for
scattering, optical, and transport experiments, but angle-resolved
photoemission spectroscopy (ARPES) data are still lacking owing to the absence
of a charge-neutral cleavage plane. We report on progress in achieving the
experimental conditions for which quasiparticles can be observed in the
near-nodal region of the Fermi surface. The d-wave superconducting gap is
measured and found to have a maximum of 39 meV. At low temperature, a kink is
detected in the nodal dispersion at approximately 51 meV below the Fermi level,
an energy that is different from other cuprates with comparable T$_c$. The
superconducting gap, Fermi surface, and nodal band renormalization measured
here provide a crucial momentum-space complement to other experimental probes.


title:
Bach-flat critical metrics of the volume functional on 4-dimensional
  manifolds with boundary

abstract:
  The purpose of this article is to investigate Bach-flat critical metrics of
the volume functional on a compact manifold $M$ with boundary $\partial M.$
Here, we prove that a Bach-flat critical metric of the volume functional on a
simply connected 4-dimensional manifold with boundary isometric to a standard
sphere must be isometric to a geodesic ball in a simply connected space form
$\Bbb{R}^{4},$ $\Bbb{H}^{4}$ or $\Bbb{S}^{4}$. Moreover, we show that in
dimension three the result even is true replacing the Bach-flat condition by
the weaker assumption that $M$ has divergence-free Bach tensor.


title: Performance Analysis of AODV, DSDV and DSR in MANETs

abstract:
  Mobile Ad hoc Networks (MANETs) are considered as a new paradigm of
infrastructure-less mobile wireless communication systems. MANETs are being
widely studied and it is the technology that is attracting a large variety of
applications. Routing in MANETs is considered a challenging task due to the
unpredictable changes in the network topology, resulting from the random and
frequent movement of the nodes and due to the absence of any centralized
control [1][2]. In this paper, we evaluate the performance of reactive routing
protocols, Ad hoc On demand Distance Vector (AODV) and Dynamic Source Routing
(DSR) and proactive routing protocol Destination Sequenced Distance Vector
(DSDV). The major goal of this study is to analyze the performance of well
known MANETs routing protocol in high mobility case under low, medium and high
density scenario. Unlike military applications, most of the other applications
of MANETs require moderate to high mobility. Hence it becomes important to
study the impact of high mobility on the performance of these routing
protocols. The performance is analyzed with respect to Average End-to-End
Delay, Normalized Routing Load (NRL), Packet Delivery Fraction (PDF) and
Throughput. Simulation results verify that AODV gives better performance as
compared to DSR and DSDV.


title: The isotropic radio background revisited

abstract:
  We present an extensive analysis on the determination of the isotropic radio
background. We consider six different radio maps, ranging from 22 MHz to 2.3
GHz and covering a large fraction of the sky. The large scale emission is
modeled as a linear combination of an isotropic component plus the Galactic
synchrotron radiation and thermal bremsstrahlung. Point-like and extended
sources are either masked or accounted for by means of a template. We find a
robust estimate of the isotropic radio background, with limited scatter among
different Galactic models. The level of the isotropic background lies
significantly above the contribution obtained by integrating the number counts
of observed extragalactic sources. Since the isotropic component dominates at
high latitudes, thus making the profile of the total emission flat, a Galactic
origin for such excess appears unlikely. We conclude that, unless a systematic
offset is present in the maps, and provided that our current understanding of
the Galactic synchrotron emission is reasonable, extragalactic sources well
below the current experimental threshold seem to account for the majority of
the brightness of the extragalactic radio sky.


title: The rebit three-tangle and its relation to two-qubit entanglement

abstract:
  The three-tangle is a measure of three-way entanglement in a system of three
qubits. For a pure state, it can be understood as the residual entanglement not
accounted for by pairwise entanglements between individual qubits. Here we
define and evaluate the analogous quantity for three rebits (that is, binary
systems in the real-amplitude variant of quantum theory). We find that the
resulting formula is the same as in the complex case, except that an overall
absolute value sign is missing. As a result, the rebit three-tangle can be
negative, expressing the possibility of non-monogamous entanglement in
real-amplitude quantum theory (for entanglement based on the convex-roof
construction). We then relate the entanglement among three rebits to the
entanglement of two qubits, by re-expressing the two-qubit state as a
three-rebit state in the ubit model.


title: Donald Arthur Preece: A life in statistics, mathematics and music

abstract:
  Biography and publications list for Donald Arthur Preece, who died on 6
January 2014, who made many contributions in statistics (experimental design)
and in combinatorics.


title: On the Dual of the Solvency Cone

abstract:
  A solvency cone is a polyhedral convex cone which is used in Mathematical
Finance to model proportional transaction costs. It consists of those
portfolios which can be traded into nonnegative positions. In this note, we
provide a characterization of its dual cone in terms of extreme directions and
discuss some consequences, among them: (i) an algorithm to construct extreme
directions of the dual cone when a corresponding "contribution scheme" is
given; (ii) estimates for the number of extreme directions; (iii) an explicit
representation of the dual cone for special cases. The validation of the
algorithm is based on the following easy-to-state but difficult-to-solve result
on bipartite graphs: Running over all spanning trees of a bipartite graph, the
number of left degree sequences equals the number of right degree sequences.


title: A Goodwillie-type Theorem for Milnor K-Theory

abstract:
  Goodwillie's rational isomorphism between relative algebraic K-theory and
relative cyclic homology, together with the lambda decomposition of cyclic
homology, illustrates the close relationships among algebraic K-theory, cyclic
homology, and differential forms. In this paper, I prove a Goodwillie-type
theorem for relative Milnor $K$-theory, working over a very general class of
commutative rings, defined via the stability criterion of Van der Kallen. Early
results of Van der Kallen and Bloch are special cases. The result likely
generalizes in terms of de Rahm-Witt complexes, by weakening some invertibility
assumptions, but the class of rings considered is already more than
sufficiently general for the intended applications. The main motivation for
this paper arises from applications to the infinitesimal theory of Chow groups,
first pointed out by Bloch in the 1970's, and prominent in recent work of Green
and Griffiths. Related results and geometric applications are discussed in the
final section.


title:
Microcanonical analysis of the Random Energy Model in a random magnetic
  field

abstract:
  We study the spin glass system consisting of a Random Energy Model coupled
with a random magnetic field. This system was investigated by de Oliveira
Filho, da Costa and Yokoi (Phys. Rev. E 74 [2006]) who computed the free
energy. In this paper, we recover their result rigorously using elementary
large deviations arguments and a conditional second moment method. Our analysis
extends at the level of fluctuations of the ground states. In particular, we
prove that the joint distribution of the extremal energies has the law of a
Poisson process with exponential density after a recentering, which is random
as opposed to the standard REM. One consequence is that the Gibbs measure of
the model exhibits a one-step replica symmetry breaking as argued by de
Oliveira Filho et al. using the replica method.


title: Characterizing the Sample Complexity of Private Learners

abstract:
  In 2008, Kasiviswanathan et al. defined private learning as a combination of
PAC learning and differential privacy. Informally, a private learner is applied
to a collection of labeled individual information and outputs a hypothesis
while preserving the privacy of each individual. Kasiviswanathan et al. gave a
generic construction of private learners for (finite) concept classes, with
sample complexity logarithmic in the size of the concept class. This sample
complexity is higher than what is needed for non-private learners, hence
leaving open the possibility that the sample complexity of private learning may
be sometimes significantly higher than that of non-private learning.
  We give a combinatorial characterization of the sample size sufficient and
necessary to privately learn a class of concepts. This characterization is
analogous to the well known characterization of the sample complexity of
non-private learning in terms of the VC dimension of the concept class. We
introduce the notion of probabilistic representation of a concept class, and
our new complexity measure RepDim corresponds to the size of the smallest
probabilistic representation of the concept class.
  We show that any private learning algorithm for a concept class C with sample
complexity m implies RepDim(C)=O(m), and that there exists a private learning
algorithm with sample complexity m=O(RepDim(C)). We further demonstrate that a
similar characterization holds for the database size needed for privately
computing a large class of optimization problems and also for the well studied
problem of private data release.


title:
Anomalous exchange interaction between intrinsic spins in conducting
  graphene systems

abstract:
  We address the nature and possible observable consequences of singular
one-electron states that appear when strong defects are introduced in the
metallic family of graphene, namely, metallic carbon nanotubes and nanotori. In
its simplest form, after creating two defects on the same sublattice, a state
may emerge at the Fermi energy presenting very unusual properties: It is
unique, normalizable, and features a wave function equally distributed around
both defects. As a result, the exchange coupling between the magnetic moments
generated by the two defects is anomalous. The intrinsic spins couple
ferromagnetically, as expected, but do not present an antiferromagnetic excited
state at any distance. We propose the use of metallic carbon nanotubes as a
novel electronic device based on this anomalous coupling between spins which
can be useful for the robust transmission of magnetic information at large
distances.


title: Reducing \theta_13 to 9 degrees

abstract:
  We propose to consider the possibility that the observed value of
$\theta_{13}$ is not the result of a correction from an initially vanishing
value, but rather the result of a correction from an initially larger value. As
an explicit example of this approach, we consider analytically and numerically
well-known CKM-like charged lepton corrections to a neutrino diagonalization
matrix that corresponds to a certain mixing scheme. Usually this results in
generating $\theta_{13} = 9^\circ$ from zero. We note here, however, that 9 is
not only given by $0 + 9$, but also by $18 - 9$. Hence, the extreme case of an
initial value of 18 degrees, reduced by charged lepton corrections to 9
degrees, is possible. For some cases under study new sum rules for the mixing
parameters, and correlations with CP phases are found.


title: The algebraic density property for affine toric varieties

abstract:
  In this paper we generalize the algebraic density property to not necessarily
smooth affine varieties relative to some closed subvariety containing the
singular locus. This property implies the remarkable approximation results for
holomorphic automorphisms of the Anders\'en-Lempert theory. We show that an
affine toric variety X satisfies this algebraic density property relative to a
closed T-invariant subvariety Y if and only if X-Y is different from T. For
toric surfaces we are able to classify those which posses a strong version of
the algebraic density property (relative to the singular locus). The main
ingredient in this classification is our proof of an equivariant version of
Brunella's famous classification of complete algebraic vector fields in the
affine plane.


title: Split Architecture for Large Scale Wide Area Networks

abstract:
  This report defines a carrier-grade split architecture based on requirements
identified during the SPARC project. It presents the SplitArchitecture
proposal, the SPARC concept for Software Defined Networking (SDN) introduced
for large-scale wide area networks such as access/aggregation networks, and
evaluates technical issues against architectural trade-offs. First we present
the control and management architecture of the proposed SplitArchitecture.
Here, we discuss a recursive control architecture consisting of hierarchically
stacked control planes and provide initial considerations regarding network
management integration to SDN in general and SplitArchitecture in particular.
Next, OpenFlow extensions to support the carrier-grade SplitArchitecture are
discussed. These are: a) Openness & Extensibility; b) Virtualization; c) OAM;
d) Resiliency approaches; e) Bootstrapping and topology discovery; f) Service
creation; g) Energy-efficient networking; h) QoS aspects; and i) Multilayer
aspects. In addition, we discuss selected deployment and adoption scenarios
faced by modern operator networks, such as service creation scenarios and
peering aspects, i.e., how to interconnect with legacy networks. Finally, we
indicate how our SplitArchitecture approach meets carrier grade scalability
requirements in access/aggregation network scenarios


title:
Equipartition magnetic fields and star formation rates in normal
  galaxies at sub-kpc scales

abstract:
  We studied the total magnetic field strength in normal star-forming galaxies
estimated using energy equipartition assumption. Using the well known
radio--far infrared correlation we demonstrate that the equipartition
assumption is valid in galaxies at sub-kpc scales. We find that the magnetic
field strength is strongly correlated with the surface star formation rate in
the galaxies NGC 6946 and NGC 5236. Further, we compare the magnetic field
energy density to the total (thermal + turbulent) energy densities of gas
(neutral + ionized) to identify regions of efficient field amplification in the
galaxy NGC 6946. We find that in regions of efficient star formation, the
magnetic field energy density is comparable to that of the total energy density
of various interstellar medium components and systematically dominates in
regions of low star formation efficiency.


title: Design of an Amplifier through Second Generation Current Conveyor

abstract:
  This paper describes the architecture of first and second generation current
conveyor (CCI and CCII respectively) and designing an amplifier using second
generation current conveyor. The designed amplifier through CCII+ can be used
in various analog computation circuits and is superior in performance than the
classical opamp. It provides better gain with higher accuracy.


title:
Compressive sensing for dynamic spectrum access networks: Techniques and
  tradeoffs

abstract:
  We explore the practical costs and benefits of CS for dynamic spectrum access
(DSA) networks. Firstly, we review several fast and practical techniques for
energy detection without full reconstruction and provide theoretical
guarantees. We also define practical metrics to measure the performance of
these techniques. Secondly, we perform comprehensive experiments comparing the
techniques on real signals captured over the air. Our results show that we can
significantly compressively acquire the signal while still accurately
determining spectral occupancy.


title: Image Search Reranking

abstract:
  The existing methods for image search reranking suffer from the
unfaithfulness of the assumptions under which the text-based images search
result. The resulting images contain more irrelevant images. Hence the re
ranking concept arises to re rank the retrieved images based on the text around
the image and data of data of image and visual feature of image. A number of
methods are differentiated for this re-ranking. The high ranked images are used
as noisy data and a k means algorithm for classification is learned to rectify
the ranking further. We are study the affect ability of the cross validation
method to this training data. The pre eminent originality of the overall method
is in collecting text/metadata of image and visual features in order to achieve
an automatic ranking of the images. Supervision is initiated to learn the model
weights offline, previous to reranking process. While model learning needs
manual labeling of the results for a some limited queries, the resulting model
is query autonomous and therefore applicable to any other query .Examples are
given for a selection of other classes like vehicles, animals and other
classes.


title: N\'eron-Severi groups of product abelian surfaces

abstract:
  We give a natural parameterization of the N\'eron-Severi group of a product
$A = E\times E'$ of two elliptic curves in terms of quadratic forms. As an
application, we determine (in the non-CM case) whether $A$ contains a smooth
curve of any fixed genus. We also determine whether $A$ admits a very ample
line bundle of any fixed degree. In particular, we determine which of these
abelian surfaces embed in $\mathbb{P}^4$, i.e. which come from the
Horrocks-Mumford bundle.


title:
Subshifts with slow complexity and simple groups with the Liouville
  property

abstract:
  We study random walk on topological full groups of subshifts, and show the
existence of infinite, finitely generated, simple groups with the Liouville
property. Results by Matui and Juschenko-Monod have shown that the derived
subgroups of topological full groups of minimal subshifts provide the first
examples of finitely generated, simple amenable groups. We show that if the
(not necessarily minimal) subshift has a complexity function that grows slowly
enough (e.g. linearly), then every symmetric and finitely supported probability
measure on the topological full group has trivial Poisson-Furstenberg boundary.
We also get explicit upper bounds for the growth of F{\o}lner sets.


title: Magnetic edge anisotropy in graphene-like honeycomb crystals

abstract:
  The independent predictions of edge ferromagnetism and the Quantum Spin Hall
phase in graphene have inspired the quest of other two dimensional honeycomb
systems, such as silicene, germanene, stanene, iridiates, and organometallic
lattices, as well as artificial superlattices, all of them with electronic
properties analogous to those of graphene, but much larger spin orbit coupling.
Here we study the interplay of ferromagnetic order and spin orbit interactions
at the zigzag edges of these graphene-like systems. We find an in-plane
magnetic anisotropy that opens a gap in the otherwise conducting edge channels,
that should result in large changes of electronic properties upon rotation of
the magnetization.


title: Curvature vs Distances: testing the FLRW cosmology

abstract:
  We test the FLRW cosmology by reconstructing in a model-independent way both
the Hubble parameter $H(z)$ and the comoving distance $D(z)$ via the most
recent Hubble and Supernovae Ia data. In particular we use: data binning with
direct error propagation, the principal component analysis, the genetic
algorithms and the Pad\'e approximation. Using our reconstructions we evaluate
the Clarkson {\it et al} test known as $\Omega_K(z)$, whose value is constant
in redshift for the standard cosmological model, but deviates elsewise. We find
good agreement with the expected values of the standard cosmological model
within the experimental errors. Finally, we provide forecasts, exploiting the
Baryon Acoustic Oscillations measurements from the Euclid survey.


title: Coordination Avoidance in Database Systems (Extended Version)

abstract:
  Minimizing coordination, or blocking communication between concurrently
executing operations, is key to maximizing scalability, availability, and high
performance in database systems. However, uninhibited coordination-free
execution can compromise application correctness, or consistency. When is
coordination necessary for correctness? The classic use of serializable
transactions is sufficient to maintain correctness but is not necessary for all
applications, sacrificing potential scalability. In this paper, we develop a
formal framework, invariant confluence, that determines whether an application
requires coordination for correct execution. By operating on application-level
invariants over database states (e.g., integrity constraints), invariant
confluence analysis provides a necessary and sufficient condition for safe,
coordination-free execution. When programmers specify their application
invariants, this analysis allows databases to coordinate only when anomalies
that might violate invariants are possible. We analyze the invariant confluence
of common invariants and operations from real-world database systems (i.e.,
integrity constraints) and applications and show that many are invariant
confluent and therefore achievable without coordination. We apply these results
to a proof-of-concept coordination-avoiding database prototype and demonstrate
sizable performance gains compared to serializable execution, notably a 25-fold
improvement over prior TPC-C New-Order performance on a 200 server cluster.


title: Information-theoretically Optimal Sparse PCA

abstract:
  Sparse Principal Component Analysis (PCA) is a dimensionality reduction
technique wherein one seeks a low-rank representation of a data matrix with
additional sparsity constraints on the obtained representation. We consider two
probabilistic formulations of sparse PCA: a spiked Wigner and spiked Wishart
(or spiked covariance) model. We analyze an Approximate Message Passing (AMP)
algorithm to estimate the underlying signal and show, in the high dimensional
limit, that the AMP estimates are information-theoretically optimal. As an
immediate corollary, our results demonstrate that the posterior expectation of
the underlying signal, which is often intractable to compute, can be obtained
using a polynomial-time scheme. Our results also effectively provide a
single-letter characterization of the sparse PCA problem.


title:
Indirect measurement of $\sin^2 \theta_W$ (or $M_W$) using $\mu^+\mu^-$
  pairs from $\gamma^*/Z$ bosons produced in $p\bar{p}$ collisions at a
  center-of-momentum energy of 1.96 TeV

abstract:
  Drell-Yan lepton pairs are produced in the process $p\bar{p} \rightarrow
\mu^+\mu^- + X$ through an intermediate $\gamma^*/Z$ boson. The
forward-backward asymmetry in the polar-angle distribution of the $\mu^-$ as a
function of the invariant mass of the $\mu^+\mu^-$ pair is used to obtain the
effective leptonic determination $\sin^2 \theta^{lept}_{eff}$ of the
electroweak-mixing parameter $\sin^2 \theta_W$, from which the value of $\sin^2
\theta_W$ is derived assuming the standard model. The measurement sample,
recorded by the Collider Detector at Fermilab (CDF), corresponds to 9.2 fb-1 of
integrated luminosity from $p\bar{p}$ collisions at a center-of-momentum energy
of 1.96 TeV, and is the full CDF Run II data set. The value of $\sin^2
\theta^{lept}_{eff}$ is found to be 0.2315 +- 0.0010, where statistical and
systematic uncertainties are combined in quadrature. When interpreted within
the context of the standard model using the on-shell renormalization scheme,
where $\sin^2 \theta_W = 1 - M_W^2/M_Z^2$, the measurement yields $\sin^2
\theta_W$ = 0.2233 +- 0.0009, or equivalently a W-boson mass of 80.365 +- 0.047
GeV/c^2. The value of the W-boson mass is in agreement with previous
determinations in electron-positron collisions and at the Tevatron collider.


title:
Analytical formulas for shear and bulk viscosities in relativistic
  gaseous mixtures with constant cross sections

abstract:
  Using Mathematica package, we derive analytical closed-form expressions for
the shear and the bulk viscosity coefficients in multicomponent relativistic
gases with constant cross sections, being the relativistic generalization for
the hard spheres model. Some of them are cumbersome and require symbolic
manipulations in an algebraic package. The constant cross sections are of the
elastic processes, while the inelastic (or number-changing) processes
(collisions or decays) are considered only partly. As examples, we find
explicit expressions of the correct single-component first-order shear
viscosity coefficient and some explicit analytical results for the binary
mixture. These formulas have numerous applications in approximate
nonequilibrium descriptions of gases of particles or quasiparticles with
averaged (temperature dependent) cross sections. In addition to this, we
present formulas for collision rates and some other related formulas. This
paper is a shortened version of a previous one.


title:
Optimization of light collection from crystal scintillators for
  cryogenic experiments

abstract:
  High light collection efficiency is an important requirement in any
application of scintillation detectors. The purpose of this study is to
investigate the possibility for improving this parameter in cryogenic
scintillation bolometers, which can be considered as a promising detectors in
experiments investigating neutrinoless double beta decay and dark matter.
Energy resolutions and relative pulse amplitudes of scintillation detectors
using ZnWO4 scintillation crystals of different shapes (cylinder 20 mm in
dimater by 20 mm and hexagonal prism with diagonal 20 mm and height 20 mm),
reflector materials and shapes, optical contact and surface properties
(polished and diffused) were measured at room temperature. Propagation of
optical photons in these experimental conditions was simulated using Geant4 and
ZEMAX codes. The results of the simulations are found to be in good agreement
with each other and with direct measurements of the crystals. This could be
applied to optimize the geometry of scintillation detectors used in the
cryogenic experiments.


title:
Stochastic differential equations for models of non-relativistic matter
  interacting with quantized radiation fields

abstract:
  We discuss Hilbert space-valued stochastic differential equations associated
with the heat semi-groups of the standard model of non-relativistic quantum
electrodynamics and of corresponding fiber Hamiltonians for translation
invariant systems. In particular, we prove the existence of a stochastic flow
satisfying the strong Markov property and the Feller property. To this end we
employ an explicit solution ansatz. In the matrix-valued case, i.e., if the
electron spin is taken into account, it is given by a series of operator-valued
time-ordered integrals, whose integrands are factorized into annihilation,
preservation, creation, and scalar parts. The Feynman-Kac formula implied by
these results is new in the matrix-valued case. Furthermore, we discuss
stochastic differential equations and Feynman-Kac representations for an
operator-valued integral kernel of the semi-group. As a byproduct we obtain
analogous results for Nelson's model.


title: Semiparametric topographical mixture models with symmetric errors

abstract:
  Motivated by the analysis of a Positron Emission Tomography (PET) imaging
data considered in Bowen et al. (2012), we introduce a semiparametric
topographical mixture model able to capture the characteristics of dichotomous
shifted response-type experiments. We propose a local estimation procedure,
based on the symmetry of the local noise, for the proportion and locations
functions involved in the proposed model. We establish under mild conditions
the minimax properties and asymptotic normality of our estimators when Monte
Carlo simulations are conducted to examine their finite sample performance.
Finally a statistical analysis of the PET imaging data in Bowen et al. (2012)
is illustrated for the proposed method.


title: S(3) flavoured Higgs model trilinear self-couplings

abstract:
  In this work, we analyze the Higgs sector of the minimal $S(3)$-invariant
extension of the Standard Model is performed. Considering three Higgs fields,
which are SU(2) doublets, and CP invariant, we compute the exact and analytical
physical Higgs boson masses in terms of the Higgs potential parameters and the
scalar Higgs matrix rotation angle $\theta_S$ and $w_3$
($\tan\theta_P=\tan\theta_C=\tan^{-1}\omega_3$), related to the pseudoscalar
and charged Higgs matrix rotation angles $\theta_P$ and $\theta_C$
respectively. Furthermore, within this model we can also write down in an
explicit form the trilinear self-couplings $\lambda_{ijk}$ in terms of the
Higgs masses and two free parameters, $\theta_S$ and $w_3$. Moreover, we show
that the Higgs masses and trilinear Higgs bosons self-couplings are closely
linked to the Higgs potential structure given by the discrete symmetry $S(3)$,
which can be helpful to distinguish this model from other extensions. In our
analysis the lightest Higgs boson mass is taken to be fixed to 125 GeV. In
concordance with the results reported in the literature for other Standard
Model extensions, it find that the numerical values $\lambda_{ijk}$ of the
minimal $S(3)$-invariant extension of the Standard Model are significantly
different from the trilinear Higgs self-coupling of the Standard Model.


title: Proof terms for infinitary rewriting, progress report

abstract:
  We generalize the notion of proof term to the realm of transfinite reduction.
Proof terms represent reductions in the first-order term format, thereby
facilitating their formal analysis. We show that any transfinite reduction can
be faithfully represented as an infinitary proof term, which is unique up to,
infinitary, associativity.
  Our main use of proof terms is in a definition of permutation equivalence for
transfinite reductions, on the basis of permutation equations. This definition
involves a variant of equational logic, adapted for dealing with infinite
objects.
  A proof of the compression property via proof terms is presented, which
establishes permutation equivalence between the original and the compressed
reductions.