title:
Stark widths of Ar III spectral lines in the atmospheres of subdwarf B
  stars

abstract:
  Using semiclassical perturbation approach in impact approximation, we have
calculated Stark widths for 32 spectral lines of doubly charged argon (Ar III).
Oscillator strengths are calculated using Hartree-Fock method with relativistic
correction (HFR) and an atomic model including 17 configurations. Energy levels
are taken from NIST database. For perturbing levels for which the corresponding
energy does not exist in NIST database, the calculated energies are used. Our
widths are compared with the experimental results. The results presented here
are of interest for modelling and investigation of stellar atmospheres since
argon in different ionization stages is observed in many astrophysical objects.
Finally, the importance of Stark broadening mechanism is studied in the
atmospheric conditions of sdB stars. Electron impact Stark widths are compared
to thermal Doppler widths as a function of temperature and optical depth of
atmospheric layers.


title: Three-loop QCD corrections to B_s -> mu^+ mu^-

abstract:
  The decay B_s -> mu^+ mu^- in the Standard Model is generated by the
well-known W-box and Z-penguin diagrams that give rise to an effective
quark-lepton operator Q_A at low energies. We compute QCD corrections of order
alpha_s^2 to its Wilson coefficient C_A. It requires performing three-loop
matching between the full and effective theories. Including the new corrections
makes C_A more stable with respect to the matching scale mu_0 at which the
top-quark mass and alpha_s are renormalized. The corresponding uncertainty in
|C_A|^2 gets reduced from around 1.8% to less than 0.2%. Our results are
directly applicable to all the B_{s(d)} -> l^+ l^- decay modes.


title: Electroweak Corrections to $B_{s,d} \to \ell^+ \ell^-$

abstract:
  We calculate the full two-loop electroweak matching corrections to the
operator governing the decay B_q --> l^+ l^- in the Standard Model. Their
inclusion removes an electroweak scheme and scale uncertainty of about 7% of
the branching ratio. Using different renormalization schemes of the involved
electroweak parameters, we estimate residual perturbative electroweak and QED
uncertainties to be less than 1% at the level of the branching ratio.


title: On the local fluctuations of last-passage percolation models

abstract:
  Using the fact that the Airy process describes the limiting fluctuations of
the Hammersley last-passage percolation model, we prove that it behaves locally
like a Brownian motion. Our method is quite straightforward, and it is based on
a certain monotonicity and good control over the equilibrium measures of the
Hammersley model (local comparison).


title:
Competing interaction in magnets: the root of ordered disorder or only
  frustration?

abstract:
  What does the equilibrium atomic, molecular or spin configuration of a glass
phase look like? Is there only one unique equilibrium configuration or are
there infinitely many configurations of equal energy? The processes and
mechanisms governing the path towards equilibrium, i.e. the dynamics of glassy
systems, provide insights to these questions. Here we discuss the intrinsic
dynamics of different glassy magnets: of spin-glasses, frustrated ferromagnets,
superspin-glasses and other nanostructured systems with competing ferro- and
antiferromagnetic interactions and randomness in their spatial distribution.
This paper is intended as a brief update on some unsolved problems and the
current empirical status in the field of disordered and frustrated magnetism.


title:
Combined action of the bound-electron nonlinearity and the
  tunnel-ionization current in low-order harmonic generation in noble gases

abstract:
  We study numerically low-order harmonic generation in noble gases pumped by
intense femtosecond laser pulses in the tunneling ionization regime. We analyze
the influence of the phase-mismatching on this process, caused by the generated
plasma, and study in dependence on the pump intensity the origin of harmonic
generation arising either from the bound-electron nonlinearity or the
tunnel-ionization current. It is shown that in argon the optimum pump intensity
of about 100 TW/cm$^2$ leads to the maximum efficiency, where the main
contribution to low-order harmonics originates from the bound-electron third
and fifth order susceptibilities, while for intensities higher than 300
TW/cm$^2$ the tunnel-ionization current plays the dominant role. Besides, we
predict that VUV pulses at 133 nm can be generated with relatively high
efficiency of about $1.5\times10^{-3}$ by 400 nm pump pulses.


title:
Nuclear Equation of State from Observations of Short Gamma-Ray Burst
  Remnants

abstract:
  The favoured progenitor model for short $\gamma$-ray bursts (SGRBs) is the
merger of two neutron stars that triggers an explosion with a burst of
collimated $\gamma$-rays. Following the initial prompt emission, some SGRBs
exhibit a plateau phase in their $X$-ray light curves that indicates additional
energy injection from a central engine, believed to be a rapidly rotating,
highly magnetised neutron star. The collapse of this `protomagnetar' to a black
hole is likely to be responsible for a steep decay in $X$-ray flux observed at
the end of the plateau. In this letter, we show that these observations can be
used to effectively constrain the equation of state of dense matter. In
particular, we show that the known distribution of masses in binary neutron
star systems, together with fits to the $X$-ray light curves, provide
constraints that exclude the softest and stiffest plausible equations of state.
We further illustrate how a future gravitational wave observation with Advanced
LIGO/Virgo can place tight constraints on the equation of state, by adding into
the picture a measurement of the chirp mass of the SGRB progenitor.


title:
Possible imprints of cosmic strings in the shadows of galactic black
  holes

abstract:
  We examine the shadow cast by a Kerr black hole pierced by a cosmic string.
The observable images depend not only on the black hole spin parameter and the
angle of inclination, but also on the deficit angle yielded by the cosmic
string. The dependence of the observable characteristics of the shadow on the
deficit angle is explored. The imprints in the black hole shadow left by the
presence of a cosmic string can serve as a method for observational detection
of such strings.


title: How to Center Binary Deep Boltzmann Machines

abstract:
  This work analyzes centered binary Restricted Boltzmann Machines (RBMs) and
binary Deep Boltzmann Machines (DBMs), where centering is done by subtracting
offset values from visible and hidden variables. We show analytically that (i)
centering results in a different but equivalent parameterization for artificial
neural networks in general, (ii) the expected performance of centered binary
RBMs/DBMs is invariant under simultaneous flip of data and offsets, for any
offset value in the range of zero to one, (iii) centering can be reformulated
as a different update rule for normal binary RBMs/DBMs, and (iv) using the
enhanced gradient is equivalent to setting the offset values to the average
over model and data mean. Furthermore, numerical simulations suggest that (i)
optimal generative performance is achieved by subtracting mean values from
visible as well as hidden variables, (ii) centered RBMs/DBMs reach
significantly higher log-likelihood values than normal binary RBMs/DBMs, (iii)
centering variants whose offsets depend on the model mean, like the enhanced
gradient, suffer from severe divergence problems, (iv) learning is stabilized
if an exponentially moving average over the batch means is used for the offset
values instead of the current batch mean, which also prevents the enhanced
gradient from diverging, (v) centered RBMs/DBMs reach higher LL values than
normal RBMs/DBMs while having a smaller norm of the weight matrix, (vi)
centering leads to an update direction that is closer to the natural gradient
and that the natural gradient is extremly efficient for training RBMs, (vii)
centering dispense the need for greedy layer-wise pre-training of DBMs, (viii)
furthermore we show that pre-training often even worsen the results
independently whether centering is used or not, and (ix) centering is also
beneficial for auto encoders.


title:
Imaginary time propagation code for large-scale two-dimensional
  eigenvalue problems in magnetic fields

abstract:
  We present a code for solving the single-particle, time-independent
Schr\"odinger equation in two dimensions. Our program utilizes the imaginary
time propagation (ITP) algorithm, and it includes the most recent developments
in the ITP method: the arbitrary order operator factorization and the exact
inclusion of a (possibly very strong) magnetic field. Our program is able to
solve thousands of eigenstates of a two-dimensional quantum system in
reasonable time with commonly available hardware. The main motivation behind
our work is to allow the study of highly excited states and energy spectra of
two-dimensional quantum dots and billiard systems with a single versatile code,
e.g., in quantum chaos research. In our implementation we emphasize a modern
and easily extensible design, simple and user-friendly interfaces, and an
open-source development philosophy.


title: On measures driven by Markov chains

abstract:
  We study measures on $[0,1]$ which are driven by a finite Markov chain and
which generalize the famous Bernoulli products. We propose a hands-on approach
to determine the structure function $\tau$ and to prove that the multifractal
formalism is satisfied. Formulas for the dimension of the measures and for the
Hausdorff dimension of their supports are also provided.


title:
Modulating charge density and inelastic optical response in graphene by
  atmospheric pressure localized intercalation through wrinkles

abstract:
  The intercalation of an oxide barrier between graphene and its metallic
substrate for chem- ical vapor deposition is a contamination-free alternative
to the transfer of graphene to dielectric supports, usually needed for the
realization of electronic devices. Low-cost pro- cesses, especially at
atmospheric pressure, are desirable but whether they are achievable remains an
open question. Combining complementary microscopic analysis, providing
structural, electronic, vibrational, and chemical information, we demonstrate
the spontaneous reactive intercalation of 1.5 nm-thick oxide ribbons between
graphene and an iridium substrate, at atmospheric pressure and room
temperature. We discover that oxygen-containing molecules needed for forming
the ribbons are supplied through the graphene wrinkles, which act as tunnels
for the efficient diffusion of molecules entering their free end. The
intercalated oxide ribbons are found to modify the graphene-support
interaction, leading to the formation of quasi-free-standing high quality
graphene whose charge density is modulated in few 10-100 nm-wide ribbons by a
few 10^12 cm-2, where the inelastic optical response is changed, due to a
softening of vibrational modes - red-shifts of Raman G and 2D bands by 6 and 10
cm-1, respectively.


title:
Scalar Compandor Design Based on Optimal Compressor Function
  Approximating by Spline Functions

abstract:
  In this paper the approximation of the optimal compressor function using the
first-degree spline functions and quadratic spline functions is done.
Coefficients on which we form approximative spline functions are determined by
solving equation systems that are formed from treshold conditions. For Gaussian
source at the input of the quantizer, using the obtained approximate spline
functions a companding quantizer designing is done. On the basis of the
comparison with the SQNR of the optimal compandor it can be noticed that the
proposed companding quantizer based on approximate spline functions achieved
SQNR arbitrary close to that of the optimal compandor.


title:
Positivity and Boundedness Preserving Schemes for Space-Time Fractional
  Predator-Prey Reaction-Diffusion Model

abstract:
  The semi-implicit schemes for the nonlinear predator-prey reaction-diffusion
model with the space-time fractional derivatives are discussed, where the space
fractional derivative is discretized by the fractional centered difference and
WSGD scheme. The stability and convergence of the semi-implicit schemes are
analyzed in the $L_\infty$ norm. We theoretically prove that the numerical
schemes are stable and convergent without the restriction on the ratio of space
and time stepsizes and numerically further confirm that the schemes have first
order convergence in time and second order convergence in space. Then we
discuss the positivity and boundedness properties of the analytical solutions
of the discussed model, and show that the numerical solutions preserve the
positivity and boundedness. The numerical example is also presented.


title: Geometric quantization of Dirac manifolds

abstract:
  We define prequantization for Dirac manifolds to generalize known procedures
for Poisson and (pre) symplectic manifolds by using characteristic
distributions obtained from 2-cocycles associated to Dirac structures. Given a
Dirac manifold $(M,D)$, we construct Poisson structure on the space of
admissible functions on $(M,D)$ and a representation of the Poisson algebra to
establish the prequantization condition of $(M,D)$ in terms of a Lie algebroid
cohomology. Additional to this, we introduce a polarization for a Dirac
manifold $M$ and discuss procedures for quantization in two cases where $M$ is
compact and where $M$ is not compact.


title: Electronic topological transition in LaSn$_3$ under pressure

abstract:
  The electronic structure, Fermi surface and elastic properties of the
iso-structural and iso-electronic LaSn$_3$ and YSn$_3$ intermetallic compounds
are studied under pressure within the framework of density functional theory
including spin-orbit coupling. The LaSn$_3$ Fermi surface consists of two
sheets, of which the second is very complex. Under pressure a third sheet
appears around compression $V/V_0=0.94$, while a small topology change in the
second sheet is seen at compression $V/V_0=0.90$. This may be in accordance
with the anomalous behaviour in the superconducting transition temperature
observed in LaSn$_3$, which has been suggested to reflect a Fermi surface
topological transition, along with a non-monotonic pressure dependence of the
density of states at the Fermi level. The same behavior is not observed in
YSn$_3$, the Fermi surface of which already includes three sheets at ambient
conditions, and the topology remains unchanged under pressure. The reason for
the difference in behaviour between LaSn$_3$ and YSn$_3$ is the role of
spin-orbit coupling and the hybridization of La - $4f$ states with the Sn - $p$
states in the vicinity of the Fermi level, which is well explained using the
band structure calculation. The elastic constants and related mechanical
properties are calculated at ambient as well as at elevated pressures. The
elastic constants increase with pressure for both compounds and satisfy the
conditions for mechanical stability under pressure.


title:
High Pressure Study of Lithium Azide from Density-Functional
  Calculations

abstract:
  The structural, electronic, optical and vibrational properties of LiN$_3$
under high pressure have been studied using plane wave pseudopotentials within
the generalized gradient approximation for the exchange and correlation
functional. The calculated lattice parameters agree quite well with
experiments. The calculated bulk modulus value is found to be 23.23 GPa which
is in good agreement with the experimental value of 20.5 GPa. Our calculations
reproduce well the trends in high pressure behavior of the structural
parameters. The present results show that the compressibility of LiN$_3$
crystal is anisotropic and the crystallographic b-axis is more compressible
when compared to a- and c-axis which is also consistent with the experiment.
The computed elastic constants clearly shows that LiN$_3$ is a mechanically
stable system and the calculated elastic constants follows the order C$_{33}$
$>$ C$_{11}$ $>$ C$_{22}$ implies that the LiN$_3$ lattice is stiffer along
c-axis and relatively weaker along b-axis. Under the application of pressure
the magnitude of the electronic band gap value decreases, indicating that the
system has the tendency to become semi conductor at high pressures. The optical
properties such as refractive index, absorption spectra and photo conductivity
along the three crystallographic directions have been calculated at ambient as
well as at high pressures. The calculated refractive index shows that the
system is optically anisotropic and the anisotropy increases with increase in
pressure. The observed peaks in the absorption and photo conductivity spectra
are found to shift towards the higher energy region as pressure increases which
imply that in LiN$_3$ decomposition is favored under pressure with the action
of light.


title:
On Known-Plaintext Attacks to a Compressed Sensing-based Encryption: A
  Quantitative Analysis

abstract:
  Despite the linearity of its encoding, compressed sensing may be used to
provide a limited form of data protection when random encoding matrices are
used to produce sets of low-dimensional measurements (ciphertexts). In this
paper we quantify by theoretical means the resistance of the least complex form
of this kind of encoding against known-plaintext attacks. For both standard
compressed sensing with antipodal random matrices and recent multiclass
encryption schemes based on it, we show how the number of candidate encoding
matrices that match a typical plaintext-ciphertext pair is so large that the
search for the true encoding matrix inconclusive. Such results on the practical
ineffectiveness of known-plaintext attacks underlie the fact that even
closely-related signal recovery under encoding matrix uncertainty is doomed to
fail.
  Practical attacks are then exemplified by applying compressed sensing with
antipodal random matrices as a multiclass encryption scheme to signals such as
images and electrocardiographic tracks, showing that the extracted information
on the true encoding matrix from a plaintext-ciphertext pair leads to no
significant signal recovery quality increase. This theoretical and empirical
evidence clarifies that, although not perfectly secure, both standard
compressed sensing and multiclass encryption schemes feature a noteworthy level
of security against known-plaintext attacks, therefore increasing its appeal as
a negligible-cost encryption method for resource-limited sensing applications.


title: Noncommutative Spacetime Realized in $AdS_{n+1}$ Space

abstract:
  In $\kappa$-Minkowski spacetime, the coordinates are Lie algebraic elements
such that time and space coordinates do not commute, whereas space coordinates
commute each other. The non-commutativity is proportional to a
Planck-length-scale constant $\kappa^{-1}$, which is a universal constant other
than the light velocity under the $\kappa$-Poincare transformation. In this
sense, the spacetime has a structure called as "Doubly Special Relativity".
Such a noncommutative structure is known to be realized by SO(1,4) generators
in 4-dimensional de Sitter space. In this paper, we try to construct a
nonommutative spacetime having commutative n-dimensional Minkowski spacetime
based on $AdS_{n+1}$ space with SO(2,n) symmetry. We also study an invariant
wave equation corresponding to the first Casimir invariant of this symmetry as
a non-local field equation expected to yield finite loop amplitudes.


title: W+W-, WZ and ZZ production in the POWHEG BOX V2

abstract:
  We present an implementation of the vector boson pair production processes
ZZ, W+W- and WZ within the POWHEG BOX V2. This implementation, derived from the
POWHEG BOX version, has several improvements over the old one, among which the
inclusion of all decay modes of the vector bosons, the possibility to generate
different decay modes in the same run, speed optimization and phase space
improvements in the handling of interference and singly resonant contributions.


title: Divisibility of Trinomials by Irreducible Polynomials over F2

abstract:
  Irreducible trinomials of given degree n over $F_2$ do not always exist and
in the cases that there is no irreducible trinomial of degree n it may be
effective to use trinomials with an irreducible factor of degree n. In this
paper we consider some conditions under which irreducible polynomials divide
trinomials over $F_2$. A condition for divisibility of self-reciprocal
trinomials by irreducible polynomials over $F_2$ is established. And we extend
Welch's criterion for testing if an irreducible polynomial divides trinomials
$x^m+x^s+1$ to the trinomials $x^{am}+x^{bs}+1$.


title: Phase transitions in dense 2-colour QCD

abstract:
  We investigate 2-colour QCD with 2 flavours of Wilson fermion at nonzero
temperature T and quark chemical potential mu, with a pion mass of 700 MeV
(m_pi/m_rho=0.8). From temperature scans at fixed mu we find that the critical
temperature for the superfluid to normal transition depends only very weakly on
mu above the onset chemical potential, while the deconfinement crossover
temperature is clearly decreasing with mu. We also present results for the
Landau-gauge gluon propagator in the hot and dense medium.


title:
Time-dependent quantum transport: causal superfermions, exact
  fermion-parity protected decay mode, and Pauli exclusion principle for mixed
  quantum states

abstract:
  We extend the recently developed causal superfermion approach to the
real-time transport theory to time-dependent decay problems.Its usefulness is
illustrated for the Anderson model of a quantum dot with tunneling rates
depending on spin due to the ferromagnetic electrodes and/or spin polarization
of the tunnel junction. We set up a second quantization scheme for density
operators in the Liouville-Fock space constructing causal field superoperators
using the fundamental physical principles of causality/probability conservation
and the fermion-parity superselection (univalence). The time-dependent
perturbation series for the time-evolution is renormalized by explicitly
performing the wide-band limit on the superoperator level. The short and
long-time reservoir correlations are shown to be tightly linked to the
occurrence of causal field destruction and creation superoperators,
respectively. The effective theory takes as a reference a damped local system,
providing an interesting starting point for numerical calculations of memory
kernels in real-time. A remarkable feature of this approach is the natural
appearance of a measurable fermion-parity protected decay mode. It already can
be calculated exactly in the Markovian, infinite temperature limit by leading
order perturbation theory, yet persists unaltered for the finite temperature,
interaction and tunneling spin polarization. Furthermore, we show how a
Liouville-space analog of the Pauli principle directly leads to the exact
result in the noninteracting limit: surprisingly, it is obtained in finite
(second) order renormalized perturbation theory, both for the self-energy as
well as the time-evolution propagator. For this limit we calculate the
time-evolution of the full density operator starting from an arbitrary initial
state on the quantum dot, including spin and pairing coherences and
two-particle correlations.


title: Hints of correlation between broad-line and radio variations for 3C 120

abstract:
  In the paper, we investigate correlation between broad-line and radio
variations for broad-line radio galaxy 3C 120. By the z-transformed discrete
correlation function method and the model-independent flux randomization/random
subset selection (FR/RSS) Monte Carlo method, we find that the broad Hbeta line
variations lead the 15 GHz variations. The FR/RSS method shows that the Hbeta
line variations lead the radio variations by a factor of tau_{ob}=0.34 +/- 0.01
yr. This time lag can be used to locate the position of emitting region of
radio outbursts in jet, on the order of ~ 5 light-years, from the central
engine. This distance is much larger than the size of broad-line region. The
large separation of the radio outburst emitting region from the broad-line
region will observably influence the gamma-ray emission in 3C 120.


title:
Anomalous quartic $WW\gamma\gamma$ and $ZZ\gamma\gamma$ couplings in
  $\gamma p$ collision at the LHC

abstract:
  We analyze the anomalous quartic gauge boson couplings $WW\gamma\gamma$ and
$ZZ\gamma\gamma$, described by dimension-6 effective quartic Lagrangian at the
LHC. The sensitivities to anomalous quartic gauge couplings
$a_{0,c}^{W,Z}/\Lambda^2$ by examining the two different photon-induced
processes $pp\to p\gamma p\to p W\gamma qX$ and $pp\to p\gamma p\to p ZZ qX$
with $W$ and $Z$s decaying leptonically are investigated. We show that $\gamma
p$ mode of photon-induced reactions at the LHC are able to probe these
couplings to the order of $10^{-6}$-$10^{-7}$ GeV$^{-2}$ at 95 % confidence
level with $\sqrt s$ = 14 TeV and for proton-proton luminosities in the range
of 30-200 fb$^{-1}$.


title:
Keldysh approach to the renormalization group analysis of the disordered
  electron liquid

abstract:
  We present a Keldysh nonlinear sigma-model approach to the renormalization
group analysis of the disordered electron liquid. We include both the Coulomb
interaction and Fermi-liquid type interactions in the singlet and triplet
channels into the formalism. Based on this model, we reproduce the coupled
renormalization group equations for the diffusion coefficient, the frequency,
and interaction constants previously derived with the replica model in the
imaginary time technique. With the help of source fields coupling to the
particle-number and spin densities, we study the density-density and spin
density-spin density correlation functions in the diffusive regime. This allows
us to obtain results for the electric conductivity and the spin susceptibility
and thereby to re-derive the main results of the one-loop renormalization group
analysis of the disordered electron liquid in the Keldysh formalism.


title:
Minimum-Variance Importance-Sampling Bernoulli Estimator for Fast
  Simulation of Linear Block Codes over Binary Symmetric Channels

abstract:
  In this paper the choice of the Bernoulli distribution as biased distribution
for importance sampling (IS) Monte-Carlo (MC) simulation of linear block codes
over binary symmetric channels (BSCs) is studied. Based on the analytical
derivation of the optimal IS Bernoulli distribution, with explicit calculation
of the variance of the corresponding IS estimator, two novel algorithms for
fast-simulation of linear block codes are proposed. For sufficiently high
signal-to-noise ratios (SNRs) one of the proposed algorithm is SNR-invariant,
i.e. the IS estimator does not depend on the cross-over probability of the
channel. Also, the proposed algorithms are shown to be suitable for the
estimation of the error-correcting capability of the code and the decoder.
Finally, the effectiveness of the algorithms is confirmed through simulation
results in comparison to standard Monte Carlo method.


title:
Observation of zero-point quantum fluctuations of a single-molecule
  magnet through the relaxation of its nuclear spin bath

abstract:
  A single-molecule magnet placed in a magnetic field perpendicular to its
anisotropy axis can be truncated to an effective two-level system, with easily
tunable energy splitting. The quantum coherence of the molecular spin is
largely determined by the dynamics of the surrounding nuclear spin bath. Here
we report the measurement of the nuclear spin--lattice relaxation in a single
crystal of the single-molecule magnet Mn$_{12}$-ac, at $T \approx 30$ mK in
perpendicular fields $B_{\perp}$ up to 9 T. Although the molecular spin is in
its ground state, we observe an increase of the nuclear relaxation rates by
several orders of magnitude up to the highest $B_{\perp}$. This unique finding
is a consequence of the zero-point quantum fluctuations of the Mn$_{12}$-ac
spin, which allow it to efficiently transfer energy from the excited nuclear
spin bath to the lattice. Our experiment highlights the importance of quantum
fluctuations in the interaction between an `effective two-level system' and its
surrounding spin bath.


title:
Ptychography imaging of the phase vortices in the x-ray beam formed by
  nanofocusing lenses

abstract:
  We present the ptychography reconstruction of the x-ray beam formed by
nanofocusing lenses (NFLs) containing a number of phase singularities
(vortices) in the vicinity of the focal plane. As a test object Siemens star
pattern was used with the finest features of 50 nm for ptychography
measurements. The extended ptychography iterative engine (ePIE) algorithm was
applied to retrieve both complex illumination and object functions from the set
of diffraction patterns. The reconstruction revealed the focus size of
91.4$\pm$1.1 nm in horizontal and 70$\pm$0.3 nm in vertical direction at full
width at half maximum (FWHM). The complex probe function was propagated along
the optical axis of the beam revealing the evolution of the phase
singularities.


title: On Realization Theory of Quantum Linear Systems

abstract:
  The purpose of this paper is to study the realization theory of quantum
linear systems. It is shown that for a general quantum linear system its
controllability and observability are equivalent and they can be checked by
means of a simple matrix rank condition. Based on controllability and
observability a specific realization is proposed for general quantum linear
systems in which an uncontrollable and unobservable subspace is identified.
When restricted to the passive case, it is found that a realization is minimal
if and only if it is Hurwitz stable. Computational methods are proposed to find
the cardinality of minimal realizations of a quantum linear passive system. It
is found that the transfer function of a quantum linear passive system $G$ can
be written as a fractional form in terms of a matrix function $\Sigma$;
moreover, $G$ is lossless bounded real if and only if $\Sigma$ is lossless
positive real. A type of realization for multi-input-multi-output quantum
linear passive systems is derived, which is closely related to its
controllability and observability decomposition. Two realizations, namely the
independent-oscillator realization and the chain-mode realization, are proposed
for single-input-single-output quantum linear passive systems, and it is shown
that under the assumption of minimal realization, the independent-oscillator
realization is unique, and these two realizations are related to the lossless
positive real matrix function $\Sigma$.


title:
Analysis of X-ray spectral variability and black hole mass determination
  of the NLS1 galaxy Mrk 766

abstract:
  We present an XMM-Newton time-resolved spectral analysis of the NLS1 galaxy
Mrk 766. We analyse eight available observations of the EPIC-pn camera taken
between May 2000 and June 2005 to investigate the X-ray spectral variability as
produced by changes in the mass accretion rate. The 0.2-10 keV spectra are
extracted in time bins longer than 3 ks to accurately trace the variations of
the best fit parameters of our adopted Comptonisation spectral model. We test a
bulk-motion Comptonisation (BMC) model which is in general applicable to any
physical system powered by accretion onto a compact object, and assumes that
soft seed photons are efficiently up-scattered via inverse Compton scattering
in a hot and dense electron corona. The Comptonised spectrum has a
characteristic power-law shape, whose slope was found to increase for large
values of the normalisation of the seed component, that is proportional to the
mass accretion rate (in Eddington units). Our baseline spectral model also
includes a warm absorber lying on the line of sight and radiation reprocessing
from the accretion disk or from outflowing matter in proximity of the central
compact object. Our study reveals that the normalisation-slope correlation,
observed in Galactic Black Hole sources (GBHs), also holds for Mrk 766:
variations of the photon index in the range Gamma~1.9-2.4 are indeed likely to
be related to the variations of m-dot, as observed in X-ray binary systems. We
finally applied a scaling technique based on the observed correlation to
estimate the BH mass in Mrk 766. This technique is commonly and successfully
applied to measure masses of GBHs, and this is the first time it is applied in
detail to estimate the BH mass in an AGN. We obtain a value of
M_{BH}=1.26^{+1.00}_{-0.77}x10^6 M_{sun} that is in very good agreement with
that estimated by the reverberation mapping


title: Size and density avalanche scaling near jamming

abstract:
  The current microscopic picture of plasticity in amorphous materials assumes
local failure events to produce displacement fields complying with linear
elasticity. Indeed, the flow properties of nonaffine systems such as foams,
emulsions and granular materials close to jamming, that produce a fluctuating
displacement fields when failing, are still controversial. Here we show, via a
thorough numerical investigation of jammed materials, that nonaffinity induces
a critical scaling of the flow properties dictated by the distance to the
jamming point. We rationalize this critical behavior introducing a new
universal jamming exponent and hyperscaling relations, and use these results to
describe the volume fraction dependence of the friction coefficient.


title:
Simulation-Based Performance Evaluation of Routing Protocols in
  Vehicular Ad-hoc Network

abstract:
  A Vehicular Ad-hoc Network (VANET) is a collection of wireless vehicle nodes
forming a temporary network without using any centralized Road Side Unit (RSU).
VANET protocols have to face high challenges due to dynamically changing
topologies and symmetric links of networks. A suitable and effective routing
mechanism helps to extend the successful deployment of vehicular ad-hoc
networks. An attempt has been made to compare the performance of two On-demand
reactive routing protocols namely AODV and DSR which works on gateway discovery
algorithms and a geographical routing protocol namely GPSR which works on an
algorithm constantly geographical based updates network topology information
available to all nodes in VANETs for different scenarios. Comparison is made on
the basis of different metrics like throughput, packet loss, packet delivery
ratio and end-to-end delay using SUMO and NS2 simulator. In this paper we have
taken different types of scenarios for simulation and then analysed the
performance results.


title:
Implementation of the frequency-modulated sideband search method for
  gravitational waves from low mass X-ray binaries

abstract:
  We describe the practical implementation of the sideband search, a search for
periodic gravitational waves from neutron stars in binary systems. The orbital
motion of the source in its binary system causes frequency-modulation in the
combination of matched filters known as the $\mathcal{F}$-statistic. The
sideband search is based on the incoherent summation of these
frequency-modulated $\mathcal{F}$-statistic sidebands. It provides a new
detection statistic for sources in binary systems, called the
$\mathcal{C}$-statistic. The search is well suited to low-mass X-ray binaries,
the brightest of which, called Sco X-1, is an ideal target candidate. For
sources like Sco X-1, with well constrained orbital parameters, a slight
variation on the search is possible. The extra orbital information can be used
to approximately demodulate the data from the binary orbital motion in the
coherent stage, before incoherently summing the now reduced number of
sidebands. We investigate this approach and show that it improves the
sensitivity of the standard Sco X-1 directed sideband search. Prior information
on the neutron star inclination and gravitational wave polarization can also be
used to improve upper limit sensitivity. We estimate the sensitivity of a Sco
X-1 directed sideband search on 10 days of LIGO data and show that it can beat
previous upper limits in current LIGO data, with a possibility of constraining
theoretical upper limits using future advanced instruments.


title:
X-ray activity cycle on the active ultra-fast rotator AB Dor A?
  Implication of correlated coronal and photometric variability

abstract:
  Although chromospheric activity cycles have been studied in a larger number
of late-type stars for quite some time, very little is known about coronal
activity-cycles in other stars and their similarities or dissimilarities with
the solar activity cycle. While it is usually assumed that cyclic activity is
present only in stars of low to moderate activity, we investigate whether the
ultra-fast rotator AB Dor, a K dwarf exhibiting signs of substantial magnetic
activity in essentially all wavelength bands, exhibits a X-ray activity cycle
in analogy to its photospheric activity cycle of about 17 years and possible
correlations between these bands. We analysed the combined optical photometric
data of AB Dor A, which span ~35 years. Additionally, we used ROSAT and
XMM-Newton X-ray observations of AB Dor A to study the long-term evolution of
magnetic activity in this active K dwarf over nearly three decades and searched
for X-ray activity cycles and related photometric brightness changes. AB Dor A
exhibits photometric brightness variations ranging between 6.75 < Vmag < 7.15
while the X-ray luminosities range between 29.8 < log LX [erg/s] < 30.2 in the
0.3-2.5 keV. As a very active star, AB Dor A shows frequent X-ray flaring, but,
in the long XMM-Newton observations a kind of basal state is attained very
often. This basal state probably varies with the photospheric activity-cycle of
AB Dor A which has a period of ~17 years, but, the X-ray variability amounts at
most to a factor of ~2, which is, much lower than the typical cycle amplitudes
found on the Sun.


title: On the duality between p-Modulus and probability measures

abstract:
  Motivated by recent developments on calculus in metric measure spaces
$(X,\mathsf d,\mathfrak m)$, we prove a general duality principle between
Fuglede's notion of $p$-modulus for families of finite Borel measures in
$(X,\mathsf d)$ and probability measures with barycenter in $L^q(X,\mathfrak
m)$, with $q$ dual exponent of $p\in (1,\infty)$. We apply this general duality
principle to study null sets for families of parametric and non-parametric
curves in $X$. In the final part of the paper we provide a new proof,
independent of optimal transportation, of the equivalence of notions of weak
upper gradient based on $p$-Modulus (Koskela-MacManus '98, Shanmugalingam '00)
and suitable probability measures in the space of curves (Ambrosio-Gigli-Savare
'11)


title:
New Periodic Solutions for Some Planar $N+3$-Body Problems with
  Newtonian Potentials

abstract:
  For some planar Newtonian $N+3$-body problems, we use variational
minimization methods to prove the existence of new periodic solutions
satisfying that $N$ bodies chase each other on a curve, and the other 3 bodies
chase each other on another curve. From the definition of the group action in
equations $(3.1)-(3.3)$, we can find that they are new solutions which are also
different from all the examples of Ferrario and Terracini (2004)$[22]$.


title: Positions of characters in finite groups and the Taketa inequality

abstract:
  We define the position of an irreducible complex character of a finite group
as an alternative to the degree. We then use this to define three classes of
groups: PR-groups, IPR-groups and weak IPR-groups. We show that IPR-groups and
weak IPR-groups are solvable and satisfy the Taketa inequality (ie, that the
derived length of the group is at most the number of degrees of irreducible
complex characters of the group), and we show that any M-group is a weak
IPR-group. We also show that even though PR-groups need not be solvable, they
cannot be perfect.


title:
How dielectric screening in two-dimensional crystals affects the
  convergence of excited-state calculations: Monolayer MoS$_2$

abstract:
  We present first-principles many-body calculations of the dielectric
constant, quasiparticle band structure, and optical absorption spectrum of
monolayer MoS$_2$ using a supercell approach. As the separation between the
periodically repeated layers is increased, the dielectric function of the layer
develops a strong $q$ dependence around $q=0$. This implies that denser
$k$-point grids are required to converge the band gap and exciton binding
energies when large supercells are used. In the limit of infinite layer
separation, here obtained using a truncated Coulomb interaction, a $45\times45$
$k$-point grid is needed to converge the G$_0$W$_0$ band gap and exciton energy
to within 0.1 eV. We provide an extensive comparison with previous studies and
explain agreement and variations in the results. It is demonstrated that too
coarse $k$-point sampling and the interactions between the repeated layers have
opposite effects on the band gap and exciton energy, leading to a fortuitous
error cancellation in the previously published results.


title:
High-precision 2MASS JHKs light curves and other data for RR Lyrae star
  SDSS J015450+001501: strong constraints for non-linear pulsation models

abstract:
  We present and discuss an extensive data set for the non-Blazhko ab-type RR
Lyrae star SDSSJ015450+001501, including optical SDSS ugriz light curves and
spectroscopic data, LINEAR and CSS unfiltered optical light curves, and
infrared 2MASS JHKs and WISE W1 and W2 light curves. Most notably, light curves
obtained by 2MASS include close to 9000 photometric measures collected over 3.3
years and provide exceedingly precise view of near-IR variability. These data
demonstrate that static atmosphere models are insufficient to explain
multi-band photometric light curve behavior and present strong constraints for
non-linear pulsation models for RR Lyrae stars. It is a challenge to modelers
to produce theoretical light curves that can explain data presented here, which
we make publicly available.


title:
Pressure-Temperature-Magnetic Field Phase Diagram of Ferromagnetic Kondo
  Lattice CeRuPO

abstract:
  We report the temperature-pressure-magnetic field phase diagram made from
electrical resistivity measurements for the ferromagnetic (FM) Kondo lattice
CeRuPO. The ground state at zero field changes from the FM state to another
state, which is suggested to be an antiferromagnetic (AFM) state, above ~0.7
GPa, and the magnetically ordered state is completely suppressed at ~2.8 GPa.
In addition to the collapse of the AFM state under pressure and a magnetic
field, a metamagnetic (MM) transition from a paramagnetic state to a polarized
paramagnetic state appears. CeRuPO will give us a rich playground for
understanding the mechanism of the MM transition under comparable FM and AFM
correlations in the Kondo lattice.


title:
Effects of a scalar field on the thermodynamics of interuniversal
  entanglement

abstract:
  We consider a multiverse scenario made up of classically disconnected regions
of the space-time that are, nevertheless, in a quantum entangled state. The
addition of a scalar field enriches the model and allows us to treat both the
inflationary and the `oscillatory stage' of the universe on the same basis.
Imposing suitable boundary conditions on the state of the multiverse, two
different representations are constructed related by a Bogoliubov
transformation. We compute the thermodynamic magnitudes of the entanglement,
such as entropy and energy, explore the effects introduced by the presence of
the scalar field and compare with previous results in the absence of scalar
field.


title:
Exponential quadrature rules for linear fractional differential
  equations

abstract:
  This paper focuses on the numerical solution of initial value problems for
fractional differential equations of linear type. The approach we propose
grounds on expressing the solution in terms of some integral weighted by a
generalized Mittag-Leffler function. Then suitable quadrature rules are devised
and order conditions of algebraic type are derived. Theoretical findings are
validated by means of numerical experiments and the effectiveness of the
proposed approach is illustrated by means of comparisons with other standard
methods.


title:
The elementary symmetric functions of reciprocals of the elements of
  arithmetic progressions

abstract:
  Let $a$ and $b$ be positive integers. In 1946, Erd\H{o}s and Niven proved
that there are only finitely many positive integers $n$ for which one or more
of the elementary symmetric functions of $1/b, 1/(a+b),..., 1/(an-a+b)$ are
integers. In this paper, we show that for any integer $k$ with $1\le k\le n$,
the $k$-th elementary symmetric function of $1/b, 1/(a+b),..., 1/(an-a+b)$ is
not an integer except that either $b=n=k=1$ and $a\ge 1$, or $a=b=1, n=3$ and
$k=2$. This refines the Erd\H{o}s-Niven theorem and answers an open problem
raised by Chen and Tang in 2012.


title: Distribution amplitudes of light-quark mesons from lattice QCD

abstract:
  We exploit a method introduced recently to determine parton distribution
amplitudes (PDAs) from minimal information in order to obtain light-quark
pseudoscalar and vector meson PDAs from the limited number of moments produced
by numerical simulations of lattice-regularised QCD. Within errors, the PDAs of
pseudoscalar and vector mesons constituted from the same valence quarks are
identical; they are concave functions, whose dilation expresses the strength of
dynamical chiral symmetry breaking; and SU(3)-flavour symmetry is broken
nonperturbatively at the level of 10%. Notably, the appearance of precision in
the lattice moments is misleading. The moments also exhibit material dependence
on lattice volume, especially for the pion. Improvements need therefore be made
before an accurate, unified picture of the light-front structure of light-quark
pseudoscalar and vector mesons is revealed.


title: Elementary coordinatization of finitely generated nilpotent groups

abstract:
  This paper has two main parts. In the first part we develop an elementary
coordinatization for any nilpotent group $G$ taking exponents in a binomial
principal ideal domain (PID) $A$. In case that the additive group $A^+$ of $A$
is finitely generated we prove using a classical result of Julia Robinson that
one can obtain a central series for $G$ where the action of the ring of
integers $\Z$ on the quotients of each of the consecutive terms of the series
except for one very specific gap, called the special gap, is interpretable in
$G$. Then we use a refinement of this central series to give a criterion for
elementary equivalence of finitely generated nilpotent groups in terms of the
relationship between group extensions and the second cohomology group.


title:
On sets minimizing their weighted length in uniformly convex separable
  Banach spaces

abstract:
  We study existence and partial regularity relative to the weighted Steiner
problem in Banach spaces. We show $C^1$ regularity almost everywhere for almost
minimizing sets in uniformly rotund Banach spaces whose modulus of uniform
convexity verifies a Dini growth condition.


title: Metric entropy, n-widths, and sampling of functions on manifolds

abstract:
  We first investigate on the asymptotics of the Kolmogorov metric entropy and
nonlinear n-widths of approximation spaces on some function classes on
manifolds and quasi-metric measure spaces. Secondly, we develop constructive
algorithms to represent those functions within a prescribed accuracy. The
constructions can be based on either spectral information or scattered samples
of the target function. Our algorithmic scheme is asymptotically optimal in the
sense of nonlinear n-widths and asymptotically optimal up to a logarithmic
factor with respect to the metric entropy.


title:
On chaoticity of the sum of chaotic shifts with their adjoints in
  Hilbert space and applications to some chaotic weighted shifts acting on some
  Fock-Bargmann spaces

abstract:
  This article is intended to outline some the recent work by the author on the
chaoticity of some specific bakward shift unbounded operators realized as
differential operators acting on some Fock-Bargmann spaces and give suficient
conditions on a linear unbounded densely defined chaotic shift operator $T$
acting on a Hilbert space for the operator $T+T^*$ to be chaotic where $T^*$ is
its adjoint.


title: Nominal Coalgebraic Data Types with Applications to Lambda Calculus

abstract:
  We investigate final coalgebras in nominal sets. This allows us to define
types of infinite data with binding for which all constructions automatically
respect alpha equivalence. We give applications to the infinitary lambda
calculus.


title: Quantum Ergodicity for Point Scatterers on Arithmetic Tori

abstract:
  We prove an analogue of Shnirelman, Zelditch and Colin de Verdiere's Quantum
Ergodicity Theorems in a case where there is no underlying classical
ergodicity. The system we consider is the Laplacian with a delta potential on
the square torus. There are two types of wave functions: old eigenfunctions of
the Laplacian, which are not affected by the scatterer, and new eigenfunctions
which have a logarithmic singularity at the position of the scatterer. We prove
that a full density subsequence of the new eigenfunctions equidistribute in
phase space. Our estimates are uniform with respect to the coupling parameter,
in particular the equidistribution holds for both the weak and strong coupling
quantizations of the point scatterer.


title: Conservation laws for the Cattaneo heat propagation

abstract:
  In this work we determine for the Cattaneo heat propagation system all the
supplementary balance laws (conservation laws) of the same order (zero) as the
system itself and extract the constitutive relations (expression for the
internal energy) dictated by the Entropy Principle. The space of all
supplementary balance laws (having the functional dimension 8) contains four
original balance laws and their deformations depending on 4 functions of
temperature $\theta$ - $\lambda(\theta),K^{A}(\theta),A=1,2,3$. The
requirements of the II law of thermodynamics leads to the exclusion of three of
these functions ($K^A$) and to further restriction to the form of internal
energy. In its final formulation, entropy balance represent the deformation of
the energy balance law by the functional parameter $\lambda (\theta)$.


title: An explicit formula for the prime counting function

abstract:
  In this paper we use a theorem first proved by S.W.Golomb and a famous
inequality by J.B. Rosser and L.Schoenfeld in order to prove that there exists
an exact formula for $\pi(n)$ which holds infinitely often.


title: Detecting cosmic rays with the LOFAR radio telescope

abstract:
  The low frequency array (LOFAR), is the first radio telescope designed with
the capability to measure radio emission from cosmic-ray induced air showers in
parallel with interferometric observations. In the first $\sim
2\,\mathrm{years}$ of observing, 405 cosmic-ray events in the energy range of
$10^{16} - 10^{18}\,\mathrm{eV}$ have been detected in the band from $30 -
80\,\mathrm{MHz}$. Each of these air showers is registered with up to
$\sim1000$ independent antennas resulting in measurements of the radio emission
with unprecedented detail. This article describes the dataset, as well as the
analysis pipeline, and serves as a reference for future papers based on these
data. All steps necessary to achieve a full reconstruction of the electric
field at every antenna position are explained, including removal of radio
frequency interference, correcting for the antenna response and identification
of the pulsed signal.


title:
The Propensity Score Estimation in the Presence of Length-biased
  Sampling: A Nonparametric Adjustment Approach

abstract:
  The pervasive use of prevalent cohort studies on disease duration,
increasingly calls for appropriate methodologies to account for the biases that
invariably accompany samples formed by such data. It is well-known, for
example, that subjects with shorter lifetime are less likely to be present in
such studies. Moreover, certain covariate values could be preferentially
selected into the sample, being linked to the long-term survivors. The existing
methodology for estimation of the propensity score using data collected on
prevalent cases requires the correct conditional survival/hazard function given
the treatment and covariates. This requirement can be alleviated if the disease
under study has stationary incidence, the so-called stationarity assumption. We
propose a nonparametric adjustment technique based on a weighted estimating
equation for estimating the propensity score which does not require modeling
the conditional survival/hazard function when the stationarity assumption
holds. Large sample properties of the estimator is established and its small
sample behavior is studied via simulation.


title: A Class of Morse Functions on Flag Manifolds

abstract:
  Given a positive definite symmetric matrix in one of the groups SL(n, R) or
Sp(n, R), we analyse its actions on Flag Manifolds, proving these are
diffeomorphisms which admit as strict Lyapunov functions a special class of
quadratic functions, all of them Z2 -perfect Morse functions. Stratifications
on the Flag Manifolds are provided which are invariant under both the
diffeomorphisms and the gradient flows of the Lyapunov functions.


title: Isotropy theorem for arbitrary-spin cosmological fields

abstract:
  We show that the energy-momentum tensor of homogeneous fields of arbitrary
spin in an expanding universe is always isotropic in average provided the
fields remain bounded and evolve rapidly compared to the rate of expansion. An
analytic expression for the average equation of state is obtained for
Lagrangians with generic power-law kinetic and potential terms. As an example
we consider the behavior of a spin-two field in the standard Fierz-Pauli theory
of massive gravity. The results can be extended to general space-time
geometries for locally inertial observers.


title: 4DAO Cookbook

abstract:
  4DAO is a FORTRAN code designed to launch automatically DAOSPEC (Stetson &
Pancino 2008) for a large sample of spectra. The main aims of 4DAO are: (1) to
allow an analysis cascade of a list of spectra provided in input, by
automatically writing the input DAOSPEC files and managing its output files;
(2) to optimize automatically some spectral parameters used by DAOSPEC in the
process of equivalent width measurement, above all the Full Width Half Maximum;
(3) to mask some spectral regions (telluric lines, interstellar features,
photospheric lines with prominent Lorenztian wings) that can bias the correct
equivalent width measurement; (4) to provide suitable graphical tools in order
to evaluate the quality of the solution, especially of the Gaussian fit to each
individual spectral line; (5) to provide the final normalized, zero radial
velocity spectra.


title: Constraining the range of Yukawa gravity interaction from S2 star orbits

abstract:
  We consider possible signatures for Yukawa gravity within the Galactic
Central Parsec, based on our analysis of the S2 star orbital precession around
the massive compact dark object at the Galactic Centre, and on the comparisons
between the simulated orbits in Yukawa gravity and two independent sets of
observations. Our simulations resulted in strong constraints on the range of
Yukawa interaction $\Lambda$ and showed that its most probable value in the
case of S2 star is around 5000 - 7000 AU. At the same time, we were not able to
obtain reliable constrains on the universal constant $\delta$ of Yukawa
gravity, because the current observations of S2 star indicated that it may be
highly correlated with parameter $\Lambda$ in the range $(0 <\delta < 1)$. For
$\delta > 2$ they are not correlated. However, the same universal constant
which was successfully applied to clusters of galaxies and rotation curves of
spiral galaxies ($\delta=1/3$) also gives a satisfactory agreement with the
observed orbital precession of the S2 star, and in that case the most probable
value for the scale parameter is $\Lambda \approx 3000 \pm 1500$ AU. Also, the
Yukawa gravity potential induces precession of S2 star orbit in the same
direction as General Relativity for $\delta > 0$ and for $\delta < -1$, and in
the opposite direction for $-1 <\delta < 0$. The future observations with
advanced facilities, such as GRAVITY or/and European Extremely Large Telescope,
are needed in order to verify these claims.


title: Sharp results for the Weyl product on modulation spaces

abstract:
  We give sufficient and necessary conditions on the Lebesgue exponents for the
Weyl product to be bounded on modulation spaces. The sufficient conditions are
obtained as the restriction to $N=2$ of a result valid for the $N$-fold Weyl
product. As a byproduct, we obtain sharp conditions for the twisted convolution
to be bounded on Wiener amalgam spaces.


title: TOP-SPIN: TOPic discovery via Sparse Principal component INterference

abstract:
  We propose a novel topic discovery algorithm for unlabeled images based on
the bag-of-words (BoW) framework. We first extract a dictionary of visual words
and subsequently for each image compute a visual word occurrence histogram. We
view these histograms as rows of a large matrix from which we extract sparse
principal components (PCs). Each PC identifies a sparse combination of visual
words which co-occur frequently in some images but seldom appear in others.
Each sparse PC corresponds to a topic, and images whose interference with the
PC is high belong to that topic, revealing the common parts possessed by the
images. We propose to solve the associated sparse PCA problems using an
Alternating Maximization (AM) method, which we modify for purpose of
efficiently extracting multiple PCs in a deflation scheme. Our approach attacks
the maximization problem in sparse PCA directly and is scalable to
high-dimensional data. Experiments on automatic topic discovery and category
prediction demonstrate encouraging performance of our approach.


title: The L1 norm of the generalized de la Vallee Poussin kernel

abstract:
  Charles de la Vall'ee Poussin defined two different kernels that bear his
name. This paper considers the one are a linear combinations of two Fej'er
kernels, which are known as the delayed means. We show that the $L^1$ norms are
constant in families of delayed means, and determine the exact value


title: Using boundaries to find smooth norms

abstract:
  The aim of this paper is to present a tool used to show that certain Banach
spaces can be endowed with $C^k$ smooth equivalent norms. The hypothesis uses
particular countable decompositions of certain subsets of $B_{X^*}$, namely
boundaries. Of interest is that the main result unifies two quite well known
results. In the final section, some new corollaries are given.


title: On Lagrangians of Hypergraphs Containing Dense Subgraphs

abstract:
  Motzkin and Straus established a remarkable connection between the maximum
clique and the Lagrangian of a graph in 1965. This connection and its
extensions were successfully employed in optimization to provide heuristics for
the maximum clique number in graphs. It is useful in practice if similar
results hold for hypergraphs. In this paper, we provide upper bounds on the
Lagrangian of a hypergraph containing dense subgraphs when the number of edges
of the hypergraph is in certain ranges. These results support a pair of
conjectures introduced by Y. Peng and C. Zhao (2012) and extend a result of J.
Talbot (2002). \keywords{Cliques of hypergraphs \and Colex ordering \and
Lagrangians of hypergraphs \and Polynomial optimization}


title: The efficiency of quantum tomography based on photon detection

abstract:
  We propose a general methodology for efficient statistical reconstruction of
a quantum state through collection and analysis of photon counting statistics.
Our approach includes both strict quantitative criteria for adequacy and
completeness of the statistical inverse problem, as well as a simple and
reliable method for evaluating errors in the reconstructed state and
approximation of a quantum state by means of the reduced finite-dimensional
model.


title: Effective Secrecy: Reliability, Confusion and Stealth

abstract:
  A security measure called effective security is defined that includes strong
secrecy and stealth communication. Effective secrecy ensures that a message
cannot be deciphered and that the presence of meaningful communication is
hidden. To measure stealth we use resolvability and relate this to binary
hypothesis testing. Results are developed for wire-tap channels and broadcast
channels with confidential messages.


title: A note on conformal equivalences

abstract:
  A new characterization of conformal transformations is given. By use of this,
the general form of conformal transformation on two-dimensional Minkowski space
is given and its conformal structure is analyzed.


title:
Achieving Both High Power and Energy Density in Electrochemical
  Supercapacitors with Nanoporous Graphene Materials

abstract:
  Supercapacitors, based on the fast ion transportation, are specialized to
provide high power, long stability, and efficient energy storage with highly
porous electrode materials. However, their low energy density and specific
capacitance prevent them from many applications that require long duration.
Using a scalable nanoporous graphene synthesis method involving a simple
annealing process in hydrogen, here we show graphene supercapacitors capable of
achieving a high energy density comparable to what Li-ion batteries can offer,
but a much higher power density. Ultra-high specific gravimetric and volumetric
capacitances are achieved with highly porous graphene electrodes. Moreover, the
supercapacitors assembled with graphene electrodes show excellent stability.
Our results demonstrate that by synthesizing graphene materials with an ideal
pore size, uniformity, and good ion accessibility, the performance of
supercapacitors can be revolutionized.


title: A continuous deRham antidifferential

abstract:
  Let M be a manifold, possibly with boundary. We show that the deRham
differential from k-forms to exact (k+1)-forms has a continuous right inverse
when both spaces are given the weak Whitney topology. This antidifferential
operator is given a fairly explicit formula depending on the choice of a
suitable good cover of M and local coordinates on the elements of the cover. If
the antidifferential operator is applied to a smooth family of exact forms, it
produces a smooth family of forms.


title:
Confronting current NLO parton fragmentation functions with inclusive
  charged-particle spectra at hadron colliders

abstract:
  The inclusive spectra of charged particles measured at high transverse
momenta ($p_T\gtrsim$2GeV/c) in proton-proton and proton-antiproton collisions
in the range of center-of-mass energies $\sqrt{s}=200-7000$GeV are compared
with next-to-leading order perturbative QCD calculations using seven recent
sets of parton-to-hadron fragmentation functions (FFs). Accounting for the
uncertainties in the scale choices and in the parton distribution functions, we
find that most of the theoretical predictions tend to overpredict the measured
LHC and Tevatron cross sections by up to a factor of two. We identify the
currently too-hard gluon-to-hadron FFs as the probable source of the problem,
and justify the need to refit the FFs using the available LHC and Tevatron data
in a region of transverse momenta, $p_T\gtrsim$10GeV/c, which is supposedly
free from additional non-perturbative contributions and where the scale
uncertainty is only modest.


title: Quantum Spin Hall Effect as $\mathbb{Z}_2$ Global Gauge Anomaly

abstract:
  We study the relation between the quantum spin Hall effect(QSHE) and the
$\mathbb{Z}_2$ global gauge anomaly and discover that there exists an
one-to-one correspondence between them. By constructing a two dimensional
non-abelian gauge theory whose non-abelian gauge field is the Berry connection
induced by the Bloch wave function of the quantum spin Hall system, we prove
that if the quantum spin Hall system is topologically nontrivial, the
corresponding 2D gauge theory has a global gauge anomaly. We further generalize
our discussion of the zero modes of the Dirac operator which play a central
role in our analysis. We find that the classical "spin" Hall effect also
contains a $\mathbb{Z}_2$ topological invariant which is not noticed before as
far as we know.


title: Dynamical coupling during collective animal motion

abstract:
  The measurement of information flows within moving animal groups has recently
been a topic of considerable interest, and it has become clear that the
individual(s) that drive collective movement may change over time, and that
such individuals may not necessarily always lead from the front. However,
methods to quantify the influence of specific individuals on the behaviour of
other group members and the direction of information flow in moving group, are
lacking on the level of empirical studies and theoretical models. Using high
spatio-temporal resolution GPS trajectories of foraging meerkats, Suricata
suricatta, we provide an information-theoretic framework to identify dynamical
coupling between animals independent of their relative spatial positions. Based
on this identification, we then compare designations of individuals as either
drivers or responders against designations provided by the relative spatial
position. We find that not only does coupling occur both from the frontal to
the trailing individuals and vice versa, but also that the coupling direction
is a non-linear function of the relative position. This provides evidence for
(i) intermittent fluctuation of the coupling strength and (ii) alternation in
the coupling direction within foraging meerkat pairs. The framework we
introduce allows for a detailed description of the dynamical patterns of mutual
influence between all pairs of individuals within moving animal groups. We
argue that applying an information-theoretic perspective to the study of
coordinated phenomena in animal groups will eventually help to understand cause
and effect in collective behaviour.


title:
High-energy neutrino signals from the Sun in dark matter scenarios with
  internal bremsstrahlung

abstract:
  We investigate the prospects to observe a high energy neutrino signal from
dark matter annihilations in the Sun in scenarios where the dark matter is a
Majorana fermion that couples to a quark and a colored scalar via a Yukawa
coupling. In this minimal scenario, the dark matter capture and annihilation in
the Sun can be studied in a single framework. We find that, for small and
moderate mass splitting between the dark matter and the colored scalar, the
two-to-three annihilation $q \bar q g$ plays a central role in the calculation
of the number of captured dark matter particles. On the other hand, the
two-to-three annihilation into $q \bar q Z$ gives, despite its small branching
fraction, the largest contribution to the neutrino flux at the Earth at the
highest energies. We calculate the limits on the model parameters using IceCube
observations of the Sun and we discuss their interplay with the requirement of
equilibrium of captures and annihilations in the Sun and with the requirement
of thermal dark matter production. We also compare the limits from IceCube to
the limits from direct detection, antiproton measurements and collider
searches.


title:
Increasing Compression Ratio of Low Complexity Compressive Sensing Video
  Encoder with Application-Aware Configurable Mechanism

abstract:
  With the development of embedded video acquisition nodes and wireless video
surveillance systems, traditional video coding methods could not meet the needs
of less computing complexity any more, as well as the urgent power consumption.
So, a low-complexity compressive sensing video encoder framework with
application-aware configurable mechanism is proposed in this paper, where novel
encoding methods are exploited based on the practical purposes of the real
applications to reduce the coding complexity effectively and improve the
compression ratio (CR). Moreover, the group of processing (GOP) size and the
measurement matrix size can be configured on the encoder side according to the
post-analysis requirements of an application example of object tracking to
increase the CR of encoder as best as possible. Simulations show the proposed
framework of encoder could achieve 60X of CR when the tracking successful rate
(SR) is still keeping above 90%.


title:
Coefficient determinants involving many Fekete-Szeg$\ddot{O}$-type
  parameters

abstract:
  We extend our definition (in a recent paper \cite{KB}) of the coefficient
determinants of analytic mappings of the unit disk to include many
Fekete-Szeg$\ddot{o}$-type parameters, and compute the best possible bounds on
certain specific determinants for the choice class of starlike functions.


title: Multiplicative differential algebraic K-theory and applications

abstract:
  We construct a version of Beilinson's regulator as a map of sheaves of
commutative ring spectra and use it to define a multiplicative variant of
differential algebraic K-theory. We use this theory to give an interpretation
of Bloch's construction of K_3-classes and the relation with dilogarithms.
Furthermore, we provide a relation to Arakelov theory via the arithmetic degree
of metrized line bundles, and we give a proof of the formality of the algebraic
K-theory of number rings.


title: Structural Learning for Template-free Protein Folding

abstract:
  The thesis is aimed to solve the template-free protein folding problem by
tackling two important components: efficient sampling in vast conformation
space, and design of knowledge-based potentials with high accuracy. We have
proposed the first-order and second-order CRF-Sampler to sample structures from
the continuous local dihedral angles space by modeling the lower and higher
order conditional dependency between neighboring dihedral angles given the
primary sequence information. A framework combining the Conditional Random
Fields and the energy function is introduced to guide the local conformation
sampling using long range constraints with the energy function.
  The relationship between the sequence profile and the local dihedral angle
distribution is nonlinear. Hence we proposed the CNF-Folder to model this
complex relationship by applying a novel machine learning model Conditional
Neural Fields which utilizes the structural graphical model with the neural
network. CRF-Samplers and CNF-Folder perform very well in CASP8 and CASP9.
  Further, a novel pairwise distance statistical potential (EPAD) is designed
to capture the dependency of the energy profile on the positions of the
interacting amino acids as well as the types of those amino acids, opposing the
common assumption that this energy profile depends only on the types of amino
acids. EPAD has also been successfully applied in the CASP 10 Free Modeling
experiment with CNF-Folder, especially outstanding on some uncommon structured
targets.


title: Unfaithful Glitch Propagation in Existing Binary Circuit Models

abstract:
  We show that no existing continuous-time, binary value-domain model for
digital circuits is able to correctly capture glitch propagation. Prominent
examples of such models are based on pure delay channels (P), inertial delay
channels (I), or the elaborate PID channels proposed by Bellido-D\'iaz et al.
We accomplish our goal by considering the solvability/non-solvability border of
a simple problem called Short-Pulse Filtration (SPF), which is closely related
to arbitration and synchronization. On one hand, we prove that SPF is solvable
in bounded time in any such model that provides channels with non-constant
delay, like I and PID. This is in opposition to the impossibility of solving
bounded SPF in real (physical) circuit models. On the other hand, for binary
circuit models with constant-delay channels, we prove that SPF cannot be solved
even in unbounded time; again in opposition to physical circuit models.
Consequently, indeed none of the binary value-domain models proposed so far
(and that we are aware of) faithfully captures glitch propagation of real
circuits. We finally show that these modeling mismatches do not hold for the
weaker eventual SPF problem.


title: A sheafification theorem for doctrines

abstract:
  We define the notion of sheaf in the context of doctrines. We prove the
associate sheaf functor theorem. We show that grothendieck toposes and toposes
obtained by the tripos to topos construction are instances of categories of
sheaves for a suitable doctrine.


title: Real-Virtual contributions to the inclusive Higgs cross-section at N3LO

abstract:
  We compute the contributions to the N3LO inclusive Higgs boson cross-section
from the square of one-loop amplitudes with a Higgs boson and three QCD partons
as external states. Our result is a Taylor expansion in the dimensional
regulator epsilon, where the coefficients of the expansion are analytic
functions of the ratio of the Higgs boson mass and the partonic center of mass
energy and they are valid for arbitrary values of this ratio. We also perform a
threshold expansion around the limit of soft-parton radiation in the final
state. The expressions for the coefficients of the threshold expansion are
valid for arbitrary values of the dimension. As a by-product of the threshold
expansion calculation, we have developed a soft expansion method at the
integrand level by identifying the relevant soft and collinear regions for the
loop-momentum.


title: Is modern science evolving in the wrong direction?

abstract:
  The present politically correct consensus is that increased exchange of
scientific insight, knowledge, practitioners and skills at the global level
brings significant benefits to all. The quantifiable scientometric changes
during the last decade, however, suggest that many areas of knowledge are
evolving in the opposite direction. Despite an increase during the last decade
of the numbers of journals and academic articles published, increases in the
number of citations the published articles receive, and increases in the number
of countries participating; important parts of the academic activity are
becoming more nationalistic. In addition, international collaboration is
decreasing in several subject areas, and in several geographic regions. For
example, countries in Asia are becoming scientifically more isolated; and
academics working in the humanities in all the regions of the world are very
nationalistic and are becoming more so. The precise consequences of this
dynamics are difficult to predict, but it certainly will have reverberations
beyond academia. The tendency of the humanities to become more provincial will
certainly not help in reducing international conflicts arising from poor
understanding of cultural differences and of diverging sociopolitical world
views. More and better data on these trends should give us a better
understanding for eventually improving academic policies worldwide.
  Keywords: International Collaboration, National, Science, Humanities, Policy


title:
Heavy-flavor electron-muon correlations in $p$$+$$p$ and $d$+Au
  collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV

abstract:
  We report $e^\pm-\mu^\mp$ pair yield from charm decay measured between
midrapidity electrons ($|\eta|<0.35$ and $p_T>0.5$ GeV/$c$) and forward
rapidity muons ($1.4<\eta<2.1$ and $p_T>1.0$ GeV/$c$) as a function of
$\Delta\phi$ in both $p$$+$$p$ and in $d$+Au collisions at
$\sqrt{s_{_{NN}}}=200$ GeV. Comparing the $p$$+$$p$ results with several
different models, we find the results are consistent with a total charm cross
section $\sigma_{c\bar{c}} =$ 538 $\pm$ 46 (stat) $\pm$ 197 (data syst) $\pm$
174 (model syst) $\mu$b. These generators also indicate that the back-to-back
peak at $\Delta\phi = \pi$ is dominantly from the leading order contributions
(gluon fusion), while higher order processes (flavor excitation and gluon
splitting) contribute to the yield at all $\Delta\phi$. We observe a
suppression in the pair yield per collision in $d$+Au. We find the pair yield
suppression factor for $2.7<\Delta\phi<3.2$ rad is $J_{dA}$ = 0.433 $\pm$ 0.087
(stat) $\pm$ 0.135 (syst), indicating cold nuclear matter modification of
$c\bar{c}$ pairs.


title:
Electronic energy loss processes for slow H and He ions in metals and
  insulators: new insights

abstract:
  Electronic stopping of H and He ions in metals and insulators is analyzed at
velocities below 0.2 atomic units, i.e. below 1 keV for H and below 4 keV for
He. In metals, stopping of H ions is affected by d-electrons only when the
d-band extends up to the Fermi energy; for He ions, also d-bands well below the
Fermi energy contribute significantly to electronic stopping. In insulators,
the low threshold velocity for electronic stopping cannot be explained by
electron-hole pair excitation; charge exchange cycles, however, may govern the
threshold behavior of electronic stopping in ionic crystals.


title: Heavy Ion Physics at the LHC: What's new ? What's next ?

abstract:
  Towards the end of 2010, some 25 years after the very first collisions of
ultra-relativistic heavy ions at fixed target energies, and some 10 years after
the start of operation of the Relativistic Heavy Ion Collider (RHIC), the LHC
opened a new era in heavy ion physics with lead on lead collisions at
$\sqrt{s_{NN}} = 2.76$ TeV. After a short reminder of the main results from
lower energies, this review highlights a few selected areas where significant
progress has been made during the first three years of ion operation at the
LHC.


title:
Characterization of poly- and single-crystal uranium-molybdenum alloy
  thin films

abstract:
  Poly- and single-crystal thin films of U-Mo alloys have been grown both on
glass and sapphire substrates by UHV magnetron sputtering. X-ray and Electron
Backscatter Diffraction data indicate that for single-crystal U1-xMox alloys,
the pure cubic uranium gamma-phase exists for x > 0.22 (10 wt.% Mo). Below 10
wt.% Mo concentration, the resulting thin film alloys exhibited a mixed
alpha-gamma uranium phase composition.


title: Lefschetz contact manifolds and odd dimensional symplectic geometry

abstract:
  In the literature, there are two different versions of Hard Lefschetz
theorems for a compact Sasakian manifold. The first version, due to
Kacimi-Alaoui, asserts that the basic cohomology of a compact Sasakian manifold
satisfies the transverse Lefschetz property. The second version, established
far more recently by Cappelletti-Montano, De Nicola, and Yudin, holds for the
De Rham cohomology of a compact Sasakian manifold. In the current paper, using
the formalism of odd dimensional symplectic geometry, we prove a Hard Lefschetz
theorem for a compact $K$-contact manifold, which implies immediately that the
two existing versions of Hard Lefschetz theorems are mathematically equivalent
to each other.
  Our method sheds new light on the Hard Lefschetz property of a Sasakian
manifold. It enables us to give a simple construction of simply-connected
$K$-contact manifolds without any Sasakian structures in any dimension $\geq
9$, and answers an open question asked by Boyer and late Galicki concerning the
existence of such examples. It also allows us to establish a sufficient and
necessary condition for a finitely presentable group to be the fundamental
group of a compact Lefschetz contact five manifold. As an immediate
application, we use it to produce first examples of compact Lefschetz contact
manifolds which do not support any Sasakian structures. This provides an answer
to another open question asked by Cappelletti-Montano, De Nicola, and Yudin in
their recent work.


title: Asymptotic Multiplicities

abstract:
  We give several new applications of our theorem on the existence of
multiplicity of graded families of ideals as a limit, including a very general
Minkowski type inequality for graded families of ideals, a very general formula
for existence of local volumes as a limit and a very general theorem on the
existence of epsilon multiplicities as a limit for modules.


title:
A topological method to characterize tapped granular media from the
  position of the particles

abstract:
  We use the first Betti number of a complex to characterize the morphological
structure of granular samples in mechanical equilibrium. We analyze
two-dimensional granular packings after a tapping process by means of both
simulations and experiments. States with equal packing fraction obtained with
different tapping intensities are distinguished after the introduction of a
filtration parameter which determines the particles (nodes in the network) that
are joined by an edge. We first use numerical simulations to characterize the
effect of the precision in the particles localization by artificially adding
different levels of noise in this magnitude. The outcomes obtained for the
simulations are then compared with the experimental results allowing a clear
distinction of experimental packings that have the same density. This is
accomplished by just using the position of the particles and no other
information about the possible contacts, or magnitude of forces.


title:
Addendum to "High order U-spin breaking: A precise amplitude relation in
  D0 decays"

abstract: Complete error analysis for first high-precision flavor test in D decays


title:
Implementation and Evaluation of Measurement-Based Admission Control
  Schemes Within a Converged Networks QoS Management Framework

abstract:
  Policy-based network management (PBNM) paradigms provide an effective tool
for end-to-end resource management in converged next generation networks by
enabling unified, adaptive and scalable solutions that integrate and
co-ordinate diverse resource management mechanisms associated with
heterogeneous access technologies. In our project, a PBNM framework for
end-to-end QoS management in converged networks is being developed. The
framework consists of distributed functional entities managed within a
policy-based infrastructure to provide QoS and resource management in converged
networks. Within any QoS control framework, an effective admission control
scheme is essential for maintaining the QoS of flows present in the network.
Measurement based admission control (MBAC) and parameter based admission
control (PBAC) are two commonly used approaches. This paper presents the
implementation and analysis of various measurement-based admission control
schemes developed within a Java-based prototype of our policy-based framework.
The evaluation is made with real traffic flows on a Linux-based experimental
testbed where the current prototype is deployed. Our results show that unlike
with classic MBAC or PBAC only schemes, a hybrid approach that combines both
methods can simultaneously result in improved admission control and network
utilization efficiency.


title:
Adaptive Measurement-Based Policy-Driven QoS Management with
  Fuzzy-Rule-based Resource Allocation

abstract:
  Fixed and wireless networks are increasingly converging towards common
connectivity with IP-based core networks. Providing effective end-to-end
resource and QoS management in such complex heterogeneous converged network
scenarios requires unified, adaptive and scalable solutions to integrate and
co-ordinate diverse QoS mechanisms of different access technologies with
IP-based QoS. Policy-Based Network Management (PBNM) is one approach that could
be employed to address this challenge. Hence, a policy-based framework for
end-to-end QoS management in converged networks, CNQF (Converged Networks QoS
Management Framework) has been proposed within our project. In this paper, the
CNQF architecture, a Java implementation of its prototype and experimental
validation of key elements are discussed. We then present a fuzzy-based CNQF
resource management approach and study the performance of our implementation
with real traffic flows on an experimental testbed. The results demonstrate the
efficacy of our resource-adaptive approach for practical PBNM systems.


title: Transverse Target Spin asymmetries in exclusive $\rho^0$ muoproduction

abstract:
  Generalized Parton Distributions (GPDs) provide a dynamical picture of the
nucleon. The exclusive production of $\rho^0$ mesons on a transversely
polarised target is sensitive to the nucleon helicity-flip GPDs $E$ which are
related to the total angular momentum of quarks and gluons. In 2007 and 2010
the COMPASS experiment at CERN collected data by scattering a 160 GeV/c muon
beam off a transversely polarised NH$_3$ target. The final state particles were
detected with the two-stage spectrometer with high resolution tracking. In this
talk new results for the azimuthal asymmetries $A_{\text{UT}}$ and
$A_{\text{LT}}$ are presented.


title:
Joint Analysis of Differential Gene Expression in Multiple Studies using
  Correlation Motifs

abstract:
  The standard methods for detecting differential gene expression are mostly
designed for analyzing a single gene expression experiment. When data from
multiple related gene expression studies are available, separately analyzing
each study is not an ideal strategy as it may fail to detect important genes
with consistent but relatively weak differential signals in multiple studies.
Jointly modeling all data allows one to borrow information across studies to
improve the analysis. However, a simple concordance model, in which each gene
is assumed to be differential in either all studies or none of the studies, is
incapable of handling genes with study-specific differential expression. In
contrast, a model that naively enumerates and analyzes all possible
differential patterns across all studies can deal with study-specificity and
allow information pooling, but the complexity of its parameter space grows
exponentially as the number of studies increases. Here we propose a
"correlation motif" approach to address this dilemma. This approach
automatically searches for a small number of latent probability vectors called
"correlation motifs" to capture the major correlation patterns among multiple
studies. The motifs provide the basis for sharing information among studies and
genes. The approach improves detection of differential expression and overcomes
the barrier of exponentially growing parameter space. It is capable of handling
all possible study-specific differential patterns in a large number of studies.
The advantages of this new approach over existing methods are illustrated using
both simulated and real data.


title:
Magnetoresistance of granular Pt-C nanostructures close to the
  metal-insulator-transition

abstract:
  We investigate the electrical and magneto-transport properties of Pt-C
granular metals prepared by focused-electron-beam induced deposition. In
particular, we consider samples close to the metal-insulator-transition
obtained from as-grown deposits by means of a low- energy electron irradiation
treatment. The temperature dependence of the conductivity shows a lnT behavior
with a transition to square root of T at low temperature, as expected for
systems in the strong-coupling tunneling regime. The magnetoresistance is
positive and is described within the wave-function shrinkage model, normally
used for disordered system in the weak-coupling regime. In order to fit the
experimental data spin-dependent tunneling has to be taken into account. In the
discussion we attribute the origin of the spin-dependency to confinement
effects of Pt nano-grains embedded in the carbon matrix.


title:
Measurement of the inclusive isolated prompt photon cross section in pp
  collisions at sqrt(s) = 7 TeV with the ATLAS detector using 4.6 fb-1

abstract:
  A measurement of the cross section for the production of isolated prompt
photons in pp collisions at a center-of-mass energy sqrt(s) = 7 TeV is
presented. The results are based on an integrated luminosity of 4.6 fb-1
collected with the ATLAS detector at the LHC. The cross section is measured as
a function of photon pseudorapidity and transverse energy in the kinematic
range between 100 GeV and 1000 GeV and in the regions of pseudorapidity less
than 1.37 and between 1.52 and 2.37. The results are compared to leading-order
parton-shower Monte Carlo models and next-to-leading-order perturbative QCD
calculations. Next-to-leading-order perturbative QCD calculations agree well
with the measured cross sections as a function of transverse energy and
pseudorapidity.


title: Magnetization dynamics of cobalt grown on graphene

abstract:
  Ferromagnetic resonance (FMR) spin pumping is a rapidly growing field which
has demonstrated promising results in a variety of material systems. This
technique utilizes the resonant precession of magnetization in a ferromagnet to
inject spin into an adjacent non-magnetic material. Spin pumping into graphene
is attractive on account of its exceptional spin transport properties. This
article reports on FMR characterization of cobalt grown on CVD graphene and
examines the validity of linewidth broadening as an indicator of spin pumping.
In comparison to cobalt samples without graphene, direct contact
cobalt-on-graphene exhibits increased FMR linewidth--an often used signature of
spin pumping. Similar results are obtained in Co/MgO/graphene structures, where
a 1nm MgO layer acts as a tunnel barrier. However, SQUID, MFM, and Kerr
microscopy measurements demonstrate increased magnetic disorder in cobalt grown
on graphene, perhaps due to changes in the growth process and an increase in
defects. This magnetic disorder may account for the observed linewidth
enhancement due to effects such as two-magnon scattering or mosaicity. As such,
it is not possible to conclude successful spin injection into graphene from FMR
linewidth measurements alone.


title: A general construction for monoid-based knapsack protocols

abstract:
  We present a generalized version of the knapsack protocol proposed by D.
Naccache and J. Stern at the Proceedings of Eurocrypt (1997). Our new framework
will allow the construction of other knapsack protocols having similar security
features. We will outline a very concrete example of a new protocol using
extension fields of a finite field of small characteristic instead of the prime
field Z/pZ, but more efficient in terms of computational costs for
asymptotically equal information rate and similar key size.


title:
Magnetic effects on spontaneous symmetry breaking/restoration in a
  toroidal topology

abstract:
  We study temperature and finite-size effects on the spontaneous symmetry
breaking/restoration for a scalar field model under the influence of an
external magnetic field, at finite chemical potential. We use the 2PI formalism
and consider the large-$N$ limit. We find that there is a minimal size of the
system to sustain the broken phase, which diminishes as the applied field
increases but is independent of the chemical potential. We analyze the critical
curves and show that the magnetic field enhances the broken-phase regions,
while increasing the chemical potential leads to a diminishement of the
critical temperature.


title: Critical behavior in the cubic dimer model at nonzero monomer density

abstract:
  We study critical behavior in the classical cubic dimer model (CDM) in the
presence of a finite density of monomers. With attractive interactions between
parallel dimers, the monomer-free CDM exhibits an unconventional transition
from a Coulomb phase to a dimer crystal. Monomers acts as charges (or
monopoles) in the Coulomb phase and, at nonzero density, lead to a standard
Landau-type transition. We use large-scale Monte Carlo simulations to study the
system in the neighborhood of the critical point, and find results in agreement
with detailed predictions of scaling theory. Going beyond previous studies of
the transition in the absence of monomers, we explicitly confirm the
distinction between conventional and unconventional criticality, and
quantitatively demonstrate the crossover between the two. Our results also
provide additional evidence for the theoretical claim that the transition in
the CDM belongs in the same universality class as the deconfined quantum
critical point in the SU(2) JQ model.


title: Fundamental limits to nanoparticle extinction

abstract:
  We show that there are shape-independent upper bounds to the extinction cross
section per unit volume of randomly oriented nanoparticles, given only material
permittivity. Underlying the limits are restrictive sum rules that constrain
the distribution of quasistatic eigenvalues. Surprisingly, optimally-designed
spheroids, with only a single quasistatic degree of freedom, reach the upper
bounds for four permittivity values. Away from these permittivities, we
demonstrate computationally-optimized structures that surpass spheroids and
approach the fundamental limits.


title: Cluster Based Cost Efficient Intrusion Detection System For Manet

abstract:
  Mobile ad-hoc networks are temporary wireless networks. Network resources are
abnormally consumed by intruders. Anomaly and signature based techniques are
used for intrusion detection. Classification techniques are used in anomaly
based techniques. Intrusion detection techniques are used for the network
attack detection process. Two types of intrusion detection systems are
available. They are anomaly detection and signature based detection model. The
anomaly detection model uses the historical transactions with attack labels.
The signature database is used in the signature based IDS schemes.
  The mobile ad-hoc networks are infrastructure less environment. The intrusion
detection applications are placed in a set of nodes under the mobile ad-hoc
network environment. The nodes are grouped into clusters. The leader nodes are
assigned for the clusters. The leader node is assigned for the intrusion
detection process. Leader nodes are used to initiate the intrusion detection
process. Resource sharing and lifetime management factors are considered in the
leader election process. The system optimizes the leader election and intrusion
detection process.
  The system is designed to handle leader election and intrusion detection
process. The clustering scheme is optimized with coverage and traffic level.
Cost and resource utilization is controlled under the clusters. Node mobility
is managed by the system.


title:
Annealed lattice animal model and Flory theory for the melt of
  non-concatenated rings: Towards the physics of crumpling

abstract:
  A Flory theory is constructed for a long polymer ring in a melt of unknotted
and non-concatenated rings. The theory assumes that the ring forms an effective
annealed branched object and computes its primitive path. It is shown that the
primitive path follows self-avoiding statistics and is characterized by the
corresponding Flory exponent of a polymer with excluded volume. Based on that,
it is shown that rings in the melt are compact objects with overall size
proportional to their length raised to the 1/3 power. Furthermore, the contact
probability exponent is estimated, albeit by a poorly controlled approximation,
with the result consistent with both numerical and experimental data.


title:
Ge Quantum Dots Encapsulated by AlAs Grown by Molecular Beam Epitaxy on
  GaAs Without Extended Defects

abstract:
  We demonstrate nearly-spherical, strain-free, self-assembled Ge quantum dots
(QDs) fully encapsulated by AlAs, grown on (100) GaAs by molecular beam epitaxy
(MBE). The QDs were formed without a wetting layer using a high temperature,
in-situ anneal. Subsequent AlAs overgrowth was free from threading dislocations
and anti-phase domains. The straddling band alignment for Ge in AlAs promises
strong and tunable confinement for both electrons and holes. The reflection
high-energy electron diffraction (RHEED) pattern changed from 2x3 to 2x5 with
anneal, which can be explained by surface reconstructions based on the
electron-counting model.


title: Construction of surfaces with large systolic ratio

abstract:
  Let $(M,g)$ be a closed, oriented, Riemannian manifold of dimension $m$. We
call a systole a shortest non-contractible loop in $(M,g)$ and denote by
$sys(M,g)$ its length. Let $SR(M,g)=\frac{{sys(M,g)}^m}{vol(M,g)}$ be the
systolic ratio of $(M,g)$. Denote by $SR(k)$ the supremum of $SR(S,g)$ among
the surfaces of fixed genus $k \neq 0$. In Section 2 we construct surfaces with
large systolic ratio from surfaces with systolic ratio close to the optimal
value $SR(k)$ using cutting and pasting techniques. For all $k_i \geq 1$, this
enables us to prove: $$\frac{1}{SR(k_1 + k_2)} \leq \frac{1}{SR(k_1)} +
\frac{1}{SR(k_2)}.$$ We furthermore derive the equivalent intersystolic
inequality for $SR_h(k)$, the supremum of the homological systolic ratio. As a
consequence we greatly enlarge the number of genera $k$ for which the bound
$SR_h(k) \geq SR(k) \gtrsim \frac{4}{9\pi} \frac{\log(k)^2}{k}$ is valid and
show that that $SR_h(k) \leq \frac{(\log(195k)+8)^2}{\pi(k-1)}$ for all $k \geq
76$. In Section 3 we expand on this idea. There we construct product manifolds
with large systolic ratio from lower dimensional manifolds.


title:
Exponential-type Inequalities Involving Ratios of the Modified Bessel
  Function of the First Kind and their Applications

abstract:
  The modified Bessel function of the first kind, $I_{\nu}(x)$, arises in
numerous areas of study, such as physics, signal processing, probability,
statistics, etc. As such, there has been much interest in recent years in
deducing properties of functionals involving $I_{\nu}(x)$, in particular, of
the ratio ${I_{\nu+1}(x)}/{I_{\nu}(x)}$, when $\nu,x\geq 0$. In this paper we
establish sharp upper and lower bounds on $H(\nu,x)=\sum_{k=1}^{\infty}
{I_{\nu+k}(x)}/{I_\nu(x)}$ for $\nu,x\geq 0$ that appears as the complementary
cumulative hazard function for a Skellam$(\lambda,\lambda)$ probability
distribution in the statistical analysis of networks. Our technique relies on
bounding existing estimates of ${I_{\nu+1}(x)}/{I_{\nu}(x)}$ from above and
below by quantities with nicer algebraic properties, namely exponentials, to
better evaluate the sum, while optimizing their rates in the regime when
$\nu+1\leq x$ in order to maintain their precision. We demonstrate the
relevance of our results through applications, providing an improvement for the
well-known asymptotic $\exp(-x)I_{\nu}(x)\sim {1}/{\sqrt{2\pi x}}$ as
$x\rightarrow \infty$, upper and lower bounding $\mathbb{P}\left[W=\nu\right]$
for $W\sim Skellam(\lambda_1,\lambda_2)$, and deriving a novel concentration
inequality on the $Skellam(\lambda,\lambda)$ probability distribution from
above and below.