title:
A functional analytic approach for a singularly perturbed Dirichlet
  problem for the Laplace operator in a periodically perforated domain

abstract:
  We consider a sufficiently regular bounded open connected subset $\Omega$ of
$\mathbb{R}^n$ such that $0 \in \Omega$ and such that $\mathbb{R}^n \setminus
\cl\Omega$ is connected. Then we choose a point $w \in ]0,1[^n$. If $\epsilon$
is a small positive real number, then we define the periodically perforated
domain $T(\epsilon) \equiv \mathbb{R}^n\setminus \cup_{z \in
\mathbb{Z}^n}\cl(w+\epsilon \Omega +z)$. For each small positive $\epsilon$, we
introduce a particular Dirichlet problem for the Laplace operator in the set
$T(\epsilon)$. More precisely, we consider a Dirichlet condition on the
boundary of the set $w+\epsilon \Omega$, and we denote the unique periodic
solution of this problem by $u[\epsilon]$. Then we show that (suitable
restrictions of) $u[\epsilon]$ can be continued real analytically in the
parameter $\epsilon$ around $\epsilon=0$.


title: On a relation between production processes and total cross sections

abstract:
  Perturbative QCD is the appropriate tool to describe many important
properties of the inclusive observables measured at electron-proton (or ion)
colliders, such as the energy dependence of the total cross sections in
well-chosen kinematical regions. This is because the electron may effectively
be replaced by its cloud of photons, whose virtualities provide a hard scale
that enables perturbative expansions.
  At hadron colliders instead, there is no hard scale in the initial state.
Therefore, the observables one may compute perturbatively involve the
production of jets, and thus belong to a quite different class of observables.
  However, it turns out that there is a formal relation between production
processes and total cross sections, enabling one to apply calculations of the
latter to the former. We review this relation, and present our recent proof
that it holds at next-to-leading order (in the BFKL sense).


title: An extension of Hsiung-Minkowski formulas and its applications

abstract:
  We prove a generalization of Hsiung-Minkowski formulas for closed
submanifolds in semi-Riemannian manifolds with constant curvature. As a
corollary, we obtain volume and area upper bounds for k-convex hypersurfaces in
terms of a weighted total k-th mean curvature of the hypersurface. We also
obtain some Alexandrov-type results and eigenvalue estimates for hypersurfaces.


title:
Comparison of secure and high capacity color image steganography
  techniques in RGB and YCbCr domains

abstract:
  Steganography is one of the methods used for secret communication.
Steganography attempts to hide the existence of the information. The object
used to hide the secret information is called as cover object. Images are the
most popular cover objects used for steganography. Different techniques have to
be used for color image steganography and grey scale image steganography since
they are stored in different ways. Color image are normally stored with 24 bit
depth and grey scale images are stored with 8 bit depth. Color images can hold
large amount of secret information since they have three color components.
Different color spaces namely RGB (Red Green Blue), HSV (Hue, Saturation,
Value), YUV, YIQ, YCbCr (Luminance, Chrominance) etc. are used to represent
color images. Color image steganography can be done in any color space domain.
In this paper color image steganography in RGB and YCbCr domain are compared.
The secret information considered is grey scale image. Since RGB is the common
method of representation, hiding secret information in this format is not
secure.


title: A random walk with heavy flavours

abstract:
  We focus on evaluating transport coefficients like drag and diffusion of
heavy quarks (HQ) passing through Quark Gluon Plasma using perturbative QCD
(pQCD). Experimental observable like nuclear suppression factor (RAA) of HQ is
evaluated for both zero and non-zero baryonic chemical potential ({\mu}_B)
scenarios using Fokker- Planck equation. Theoretical estimates of RAA are
contrasted with experiments.


title: Magnetism of sodium superoxide

abstract:
  By combining first-principles electronic-structure calculations with the
model Hamiltonian approach, we systematically study the magnetic properties of
sodium superoxide (NaO2), originating from interacting superoxide molecules. We
show that NaO2 exhibits a rich variety of magnetic properties, which are
controlled by relative alignment of the superoxide molecules as well as the
state of partially filled antibonding molecular \pi_g-orbitals. The orbital
degeneracy and disorder in the high-temperature pyrite phase gives rise to weak
isotropic antiferromagnetic (AFM) interactions between the molecules. The
transition to the low-temperature marcasite phase lifts the degeneracy, leading
to the orbital order and formation of the quasi-one-dimensional AFM spin
chains. Both tendencies are consistent with the behavior of experimental
magnetic susceptibility data. Furthermore, we evaluate the magnetic transition
temperature and type of the long-range magnetic order in the marcasite phase.
We argue that this magnetic order depends on the behavior of weak isotropic as
well as anisotropic and Dzyaloshinskii-Moriya exchange interactions between the
molecules. Finally, we predict the existence of a multiferroic phase, where the
inversion symmetry is broken by the long-range magnetic order, giving rise to
substantial ferroelectric polarization.


title: Theory of wind accretion

abstract:
  A review of wind accretion in high-mass X-ray binaries is presented. We focus
attention to different regimes of quasi-spherical accretion onto the neutron
star: the supersonic (Bondi) accretion, which takes place when the captured
matter cools down rapidly and falls supersonically toward NS magnetospghere,
and subsonic (settling) accretion which occurs when plasma remains hot until it
meets the magnetospheric boundary. Two regimes of accretion are separated by an
X-ray luminosity of about $4\times10^{36}$ erg/s. In the subsonic case, which
sets in at low luminosities, a hot quasi-spherical shell must be formed around
the magnetosphere, and the actual accretion rate onto NS is determined by
ability of the plasma to enter the magnetosphere due to Rayleigh-Taylor
instability. We calculate the rate of plasma entry the magnetopshere and the
angular momentum transfer in the shell due to turbulent viscosity appearing in
the convective differentially rotating shell. We also discuss and calculate the
structure of the magnetospheric boundary layer where the angular momentum
between the rotating magnetosphere and the base of the differentially rotating
quasi-spherical shell takes place. We show how observations of equilibrium
X-ray pulsars Vela X-1 and GX 301-2 can be used to estimate dimensionless
parameters of the subsonic settling accretion theory, and obtain the width of
the magnetospheric boundary layer for these pulsars.


title: Formal properties in small codimension

abstract:
  In this note we extend connectedness results to formal properties of inverse
images under proper maps of Schubert varieties and of the diagonal in products
of projective rational homogeneous spaces


title: A note on the characteristic rank and related numbers

abstract:
  This note quantifies, via a sharp inequality, an interplay between (a) the
characteristic rank of a vector bundle over a topological space X, (b) the
Z/2Z-Betti numbers of X, and (c) sums of the numbers of certain partitions of
integers. In a particular context, (c) is transformed into a sum of the readily
calculable Betti numbers of the real Grassmann manifolds.


title: Do we see accreting magnetars in X-ray pulsars?

abstract:
  Strong magnetic field of accreting neutron stars ($10^{14}$ G) is hard to
probe by X-ray spectroscopy but can be indirectly inferred from
spin-up/spin-down measurement in X-ray pulsars. The existing observations of
slowly rotating X-ray pulsars are discussed. It is shown that magnetic fields
of neutron stars derived from these observations (or lower limits in some
cases) fall within the standard $10^{12}$-$10^{13}$ G range. Claims about the
evidence for accreting magnetars are critically discussed in the light of
recent progress in understanding of accretion onto slowly rotating neutron
stars in the subsonic regime.


title:
QuickXsort: Efficient Sorting with n log n - 1.399n +o(n) Comparisons on
  Average

abstract:
  In this paper we generalize the idea of QuickHeapsort leading to the notion
of QuickXsort. Given some external sorting algorithm X, QuickXsort yields an
internal sorting algorithm if X satisfies certain natural conditions.
  With QuickWeakHeapsort and QuickMergesort we present two examples for the
QuickXsort-construction. Both are efficient algorithms that incur approximately
n log n - 1.26n +o(n) comparisons on the average. A worst case of n log n +
O(n) comparisons can be achieved without significantly affecting the average
case.
  Furthermore, we describe an implementation of MergeInsertion for small n.
Taking MergeInsertion as a base case for QuickMergesort, we establish a
worst-case efficient sorting algorithm calling for n log n - 1.3999n + o(n)
comparisons on average. QuickMergesort with constant size base cases shows the
best performance on practical inputs: when sorting integers it is slower by
only 15% to STL-Introsort.


title:
Impact of photoevaporative mass loss on masses and radii of water-rich
  sub/super-Earths

abstract:
  Recent progress in transit photometry opened a new window to the interior of
super-Earths. From measured radii and masses, we can infer planetary internal
compositions. It has been recently revealed that super-Earths are diverse in
composition. Such a diversity is thought to arise from diversity in volatile
content. The stability of the volatile components is to be examined, because
hot super-Earths undergo photo-evaporative mass loss. While several studies
investigated the impact of photo-evaporative mass loss on hydrogen-helium
envelopes, there are few studies as to the impact on water-vapor envelopes. To
obtain theoretical prediction to future observations, we also investigate the
relationships among masses, radii, and semimajor axes of water-rich
sub/super-Earths that have undergone photo-evaporative mass loss. We simulate
the interior structure and evolution of sub/super-Earths that consist of a
rocky core surrounded by a water envelope, including mass loss due to the
stellar XUV-driven energy-limited hydrodynamic escape. We find that the
photo-evaporative mass loss has a significant impact on the evolution of hot
sub/super-Earths. We then derive the threshold planetary mass and radius below
which the planet loses its water envelope completely as a function of the
initial water content, and find that there are minimums of the threshold mass
and radius. We constrain the domain in the parameter space of planetary mass,
radius, and semimajor axis in which sub/super-Earths never retain water
envelopes in 1-10 Gyr. This would provide an essential piece of information for
understanding the origin of close-in low-mass planets. The current
uncertainties in stellar XUV flux and its heating efficiency, however, prevent
us from deriving robust conclusions. Nevertheless, it seems to be a robust
conclusion that Kepler planet candidates contain a significant number of rocky
sub/super-Earths.


title: SST-GATE: A dual mirror telescope for the Cherenkov Telescope Array

abstract:
  The Cherenkov Telescope Array (CTA) will be the world's first open
observatory for very high energy gamma-rays. Around a hundred telescopes of
different sizes will be used to detect the Cherenkov light that results from
gamma-ray induced air showers in the atmosphere. Amongst them, a large number
of Small Size Telescopes (SST), with a diameter of about 4 m, will assure an
unprecedented coverage of the high energy end of the electromagnetic spectrum
(above ~1TeV to beyond 100 TeV) and will open up a new window on the
non-thermal sky. Several concepts for the SST design are currently being
investigated with the aim of combining a large field of view (~9 degrees) with
a good resolution of the shower images, as well as minimizing costs. These
include a Davies-Cotton configuration with a Geiger-mode avalanche photodiode
(GAPD) based camera, as pioneered by FACT, and a novel and as yet untested
design based on the Schwarzschild-Couder configuration, which uses a secondary
mirror to reduce the plate-scale and to allow for a wide field of view with a
light-weight camera, e.g. using GAPDs or multi-anode photomultipliers. One
objective of the GATE (Gamma-ray Telescope Elements) programme is to build one
of the first Schwarzschild-Couder prototypes and to evaluate its performance.
The construction of the SST-GATE prototype on the campus of the Paris
Observatory in Meudon is under way. We report on the current status of the
project and provide details of the opto-mechanical design of the prototype, the
development of its control software, and simulations of its expected
performance.


title:
Formal features of a General Theoretical Framework for Decoherence in
  open and closed systems

abstract:
  Two complementary decoherence formalisms, Environment Induced Decoherence
(EID) for open systems and Self Induced Decoherence (SID) for close systems are
compared under a common General Theoretical Formalism for Decoherence (GTFD).
The differences and similarities of EID and SID are studied, e. g. that the
main difference is that EID only considers the relevant information of the
proper system S and neglects the rest, while SID considers all possible
information available from a certain class of measurement instruments and
neglects the non available information.


title:
New Fermi-LAT event reconstruction reveals more high-energy gamma rays
  from Gamma-ray bursts

abstract:
  Based on the experience gained during the four and a half years of the
mission, the Fermi -LAT collaboration has undertaken a comprehensive revision
of the event-level analysis going under the name of Pass 8. Although it is not
yet finalized, we can test the improvements in the new event reconstruction
with the special case of the prompt phase of bright Gamma-Ray Bursts (GRBs),
where the signal to noise ratio is large enough that loose selection cuts are
sufficient to identify gamma- rays associated with the source. Using the new
event reconstruction, we have re-analyzed ten GRBs previously detected by the
LAT for which an x-ray/optical follow-up was possible and found four new gamma
rays with energies greater than 10 GeV in addition to the seven previously
known. Among these four is a 27.4 GeV gamma-ray from GRB 080916C, which has a
redshift of 4.35, thus making it the gamma ray with the highest intrinsic
energy (147 GeV) detected from a GRB. We present here the salient aspects of
the new event reconstruction and discuss the scientific implications of these
new high-energy gamma rays, such as constraining extragalactic background light
models, Lorentz invariance violation (LIV) tests, the prompt emission mechanism
and the bulk Lorentz factor of the emitting region.


title: Signatures of relativistic protons in CTA blazar spectra

abstract:
  The Cherenkov Telescope Array (CTA) will provide very-high-energy (VHE; >~30
GeV) gamma-ray spectra of unprecedented resolution over a large energy range.
It is likely that, at least for bright sources, spectral features will be
revealed that cannot be distinguished with the current generation of Cherenkov
telescopes. We are investigating the capability of the CTA to detect spectral
signatures in TeV bright BL Lac objects that could reveal the emission from a
population of relativistic protons in those sources. Such a detection would be
crucial for the long-standing question of the origin of extragalactic cosmic
rays. As a first step, the expected VHE emission from hadronic scenarios is
compared to the spectral features that might arise in the more commonly assumed
leptonic scenarios for a given source. We also evaluate the impact of different
array configurations on the detectability of such features.


title:
Barrier Height Formation in Organic Blends / Metal Interfaces: Case of
  (TTF-TCNQ) / Au(111)

abstract:
  The interface between the tetrathiafulvalene / tetracyanoquinodimethane
(TTFTCNQ) organic blend and the Au(111) metal surface is analyzed by Density
Functional Theory calculations, including the effect of the charging energies
on the molecule transport gaps. Given the strong donor and acceptor characters
of the TTF and TCNQ molecules, respectively, there is a strong intermolecular
interaction, with a relatively high charge transfer between the two organic
materials. We find that the TCNQ LUMO peak is very close to the Fermi level;
due to the interaction with the metal surface, the organic blend molecular
levels are broadened, creating an important induced density of interface
states. We show that the interface energy level alignment is controlled by the
charge transfer between TTF, TCNQ and Au, and by the molecular dipoles created
in the molecules because of their deformations when adsorbed on Au(111); in
particular the TCNQ molecules present a bent adsorption geometry with the N
atoms bonded to the Au surface. A generalization of the Unified-IDIS model, to
explain how the interface energy levels alignment is achieved for the case of
this blended organic layer, is presented by introducing matrix equations
associated with the Charge Neutrality Levels of both organic materials and with
their intermixed screening properties.


title:
Between Sense and Sensibility: Declarative narrativisation of mental
  models as a basis and benchmark for visuo-spatial cognition and computation
  focussed collaborative cognitive systems

abstract:
  What lies between `\emph{sensing}' and `\emph{sensibility}'? In other words,
what kind of cognitive processes mediate sensing capability, and the formation
of sensible impressions ---e.g., abstractions, analogies, hypotheses and theory
formation, beliefs and their revision, argument formation--- in domain-specific
problem solving, or in regular activities of everyday living, working and
simply going around in the environment? How can knowledge and reasoning about
such capabilities, as exhibited by humans in particular problem contexts, be
used as a model and benchmark for the development of collaborative cognitive
(interaction) systems concerned with human assistance, assurance, and
empowerment?
  We pose these questions in the context of a range of assistive technologies
concerned with \emph{visuo-spatial perception and cognition} tasks encompassing
aspects such as commonsense, creativity, and the application of specialist
domain knowledge and problem-solving thought processes. Assistive technologies
being considered include: (a) human activity interpretation; (b) high-level
cognitive rovotics; (c) people-centred creative design in domains such as
architecture & digital media creation, and (d) qualitative analyses geographic
information systems. Computational narratives not only provide a rich cognitive
basis, but they also serve as a benchmark of functional performance in our
development of computational cognitive assistance systems. We posit that
computational narrativisation pertaining to space, actions, and change provides
a useful model of \emph{visual} and \emph{spatio-temporal thinking} within a
wide-range of problem-solving tasks and application areas where collaborative
cognitive systems could serve an assistive and empowering function.


title:
Readout electronics of silicon detectors used in space cosmic-ray
  charges measurement

abstract:
  A readout electronics used in space cosmic-ray charges measurement for
multi-channel silicon detector and its performance test results are introduced
in this paper. A 64-channel charge sensitive ASIC (VA140) from IDEAS company is
adopt in this method. With its features of low power consumption, low noise,
large dynamic range and high integration, it can be used in future particle
detecting experiments base on silicon detector.


title: The Schwarzian derivative and the Wiman-Valiron property

abstract:
  Suppose that a transcendental meromorphic function in the plane has finitely
many critical values, while its multiple points have bounded multiplicities,
and its inverse function has finitely many transcendental singularities. Using
the Wiman-Valiron method it is shown that the Schwarzian derivative does not
have a direct transcendental singularity over infinity, and does not have
infinity as a Borel exceptional value.


title:
A two-layer Conditional Random Field for the classification of partially
  occluded objects

abstract:
  Conditional Random Fields (CRF) are among the most popular techniques for
image labelling because of their flexibility in modelling dependencies between
the labels and the image features. This paper proposes a novel CRF-framework
for image labeling problems which is capable to classify partially occluded
objects. Our approach is evaluated on aerial near-vertical images as well as on
urban street-view images and compared with another methods.


title: Electrovacuum cylindrical stationary solutions in general relativity

abstract:
  This paper presents a systematical study of stationary (rotating) cylindrical
space-times of a Weyl form that are solutions to D=4 Einstein-Maxwell equations
with cosmological constant. The corresponding equations of motion - with zero
cosmological constant - are integrated. Then, several classes of exact
solutions - obtained by restricting the range of the free constant parameters -
are obtained and sub-cases corresponding to already known solutions are
indicated.


title: Lipid ion channels and the role of proteins

abstract:
  Synthetic lipid membranes in the absence of proteins can display quantized
conduction events for ions that are virtually indistinguishable from those of
protein channel. By indistinguishable we mean that one cannot decide based on
the current trace alone whether conductance events originate from a membrane,
which does or does not contain channel proteins. Additional evidence is
required to distinguish between the two cases, and it is not always certain
that such evidence can be provided. The phenomenological similarities are
striking and span a wide range of phenomena: The typical conductances are of
equal order and both lifetime distributions and current histograms are similar.
One finds conduction bursts, flickering, and multistep-conductance. Lipid
channels can be gated by voltage, and can be blocked by drugs. They respond to
changes in lateral membrane tension and temperature. Thus, they behave like
voltage-gated, temperature-gated and mechano-sensitive protein channels, or
like receptors. Lipid channels are remarkably under-appreciated. However, the
similarity between lipid and protein channels poses an eminent problem for the
interpretation of protein channel data. For instance, the Hodgkin-Huxley theory
for nerve pulse conduction requires a selective mechanism for the conduction of
sodium and potassium ions. To this end, the lipid membrane must act both as a
capacitor and as an insulator. Non-selective ion conductance by mechanisms
other than the gated protein-channels challenges the proposed mechanism for
pulse propagation. ... Some important questions arise: Are lipid and protein
channels similar due a common mechanism, or are these similarities fortuitous?
Is it possible that both phenomena are different aspects of the same
phenomenon? Are lipid and protein channels different at all? ... (abbreviated)


title: Spatio-Temporal Queries for moving objects Data warehousing

abstract:
  In the last decade, Moving Object Databases (MODs) have attracted a lot of
attention from researchers. Several research works were conducted to extend
traditional database techniques to accommodate the new requirements imposed by
the continuous change in location information of moving objects. Managing,
querying, storing, and mining moving objects were the key research directions.
This extensive interest in moving objects is a natural consequence of the
recent ubiquitous location-aware devices, such as PDAs, mobile phones, etc., as
well as the variety of information that can be extracted from such new
databases. In this paper we propose a Spatio-Temporal data warehousing (STDW)
for efficiently querying location information of moving objects. The proposed
schema introduces new measures like direction majority and other
direction-based measures that enhance the decision making based on location
information.


title:
Linear Codes over Z_4+uZ_4: MacWilliams identities, projections, and
  formally self-dual codes

abstract:
  Linear codes are considered over the ring Z_4+uZ_4, a non-chain extension of
Z_4. Lee weights, Gray maps for these codes are defined and MacWilliams
identities for the complete, symmetrized and Lee weight enumerators are proved.
Two projections from Z_4+uZ_4 to the rings Z_4 and F_2+uF_2 are considered and
self-dual codes over Z_4+uZ_4 are studied in connection with these projections.
Finally three constructions are given for formally self-dual codes over
Z_4+uZ_4 and their Z_4-images together with some good examples of formally
self-dual Z_4-codes obtained through these constructions.


title:
Exploring high-energy processes in binary systems with the Cherenkov
  Telescope Array

abstract:
  Several types of binary systems have been detected up to now at high and very
high gamma-ray energies, including microquasars, young pulsars around massive
stars and colliding wind binaries. The study of the sources already known, and
of the new types of sources expected to be discovered with the unprecedented
sensitivity of CTA, will allow us to qualitatively improve our knowledge on
particle acceleration, emission and radiation reprocessing, and on the dynamics
of flows and their magnetic fields. Here we present some examples of the
capabilities of CTA to probe the flux and spectral changes that typically occur
in these astrophysical sources, as well as to search for delays in correlated
X-ray/TeV variability with CTA and satellites of the CTA era. Our results show
that our knowledge of the high-energy physics in binary systems will
significantly deepen with CTA.


title:
A comparative study of radio halo occurrence in SZ and X-ray selected
  galaxy cluster samples

abstract:
  We aim at an unbiased census of the radio halo population in galaxy clusters
and test whether current low number counts of radio halos have arisen from
selection biases. We construct near-complete samples based on X-ray and
Sunyaev-Zel'dovich (SZ) effect cluster catalogues and search for diffuse,
extended (Mpc-scale) emission near the cluster centers by analyzing data from
the National Radio Astronomy Observatory Very Large Array Sky Survey. We remove
compact sources using a matched filtering algorithm and model the diffuse
emission using two independent methods. The relation between radio halo power
at 1.4 GHz and mass observables is modelled using a power law, allowing for a
'dropout' population of clusters hosting no radio halo emission. An extensive
suite of simulations is used to check for biases in our methods. Our findings
suggest that the fraction of targets hosting radio halos may have to be revised
upwards for clusters selected using the SZ effect: while approximately 60 per
cent of the X-ray selected targets are found to contain no extended radio
emission, in agreement with previous findings, the corresponding fraction in
the SZ selected samples is roughly 20 per cent. We propose a simple explanation
for this selection difference based on the distinct time evolution of the SZ
and X-ray observables during cluster mergers, and a bias towards relaxed,
cool-core clusters in the X-ray selection.


title: The monomial ideal of independent sets associated to a graph

abstract:
  Independent sets play a key role into the study of graphs and important
problems arising in graph theory reduce to them. We define the monomial ideal
of independent sets associated to a finite simple graph and describe its
homological and algebraic invariants in terms of the combinatorics of the
graph. We compute the minimal primary decomposition and characterize the
Cohen--Macaulay ideals. Moreover, we provide a formula for computing the Betti
numbers, which depends only on the coefficients of the independence polynomial
of the graph.


title: Design and Implementation of Car Parking System on FPGA

abstract:
  As, the number of vehicles are increased day by day in rapid manner. It
causes the problem of traffic congestion, pollution (noise and air). To
overcome this problem A FPGA based parking system has been proposed. In this
paper, parking system is implemented using Finite State Machine modelling. The
system has two main modules i.e. identification module and slot checking
module. Identification module identifies the visitor. Slot checking module
checks the slot status. These modules are modeled in HDL and implemented on
FPGA. A prototype of parking system is designed with various interfaces like
sensor interfacing, stepper motor and LCD.


title:
A C*-algebra for quantized principal U(1)-connections on globally
  hyperbolic Lorentzian manifolds

abstract:
  The aim of this work is to complete our program on the quantization of
connections on arbitrary principal U(1)-bundles over globally hyperbolic
Lorentzian manifolds. In particular, we show that one can assign via a
covariant functor to any such bundle an algebra of observables which separates
gauge equivalence classes of connections. The C*-algebra we construct
generalizes the usual CCR-algebras since, contrary to the standard
field-theoretic models, it is based on a presymplectic Abelian group instead of
a symplectic vector space. We prove a no-go theorem according to which neither
this functor, nor any of its quotients, satisfies the strict axioms of general
local covariance. As a byproduct, we prove that a morphism violates the
locality axiom if and only if a certain induced morphism of cohomology groups
is non-injective. We then show that fixing any principal U(1)-bundle, there
exists a suitable category of sub-bundles for which a quotient of our functor
yields a quantum field theory in the sense of Haag and Kastler. We shall
provide a physical interpretation of this feature and we obtain some new
insights concerning electric charges in locally covariant quantum field theory.


title:
Night Sky Background Analysis for the Cherenkov Telescope Array using
  the Atmoscope instrument

abstract:
  The site selection group for the future Cherenkov Telescope Array (CTA) has
deployed sensitive light sensors at 9 candidate sites, 5 of them in the
Southern and 4 in the Northern hemisphere. The sensors are equipped with a PIN
diode and a calibrated V-filter, and a blue/UV filter matching the spectral
response of the photomultipliers to be employed in the CTA cameras. All sensor
installations, denominated "Atmoscopes", have been cross-calibrated before
deployment, and their sensitivity is monitored every two to five months. We
show that a thoroughly developed model of the integral contribution of
starlight to the overall light measure serves as an additional
cross-calibration for each device during each night, reducing the systematic
uncertainty of this measurement to less than 15%. The starlight can then be
subtracted from the measurements, and the residuals compared among the
different sites. We show that in most cases a decomposition into the
contributions from zodiacal light, airglow and anthropogenic light pollution is
possible.


title:
Contrast Enhancement And Brightness Preservation Using Multi-
  Decomposition Histogram Equalization

abstract:
  Histogram Equalization (HE) has been an essential addition to the Image
Enhancement world. Enhancement techniques like Classical Histogram Equalization
(CHE), Adaptive Histogram Equalization (ADHE), Bi-Histogram Equalization (BHE)
and Recursive Mean Separate Histogram Equalization (RMSHE) methods enhance
contrast, however, brightness is not well preserved with these methods, which
gives an unpleasant look to the final image obtained. Thus, we introduce a
novel technique Multi-Decomposition Histogram Equalization (MDHE) to eliminate
the drawbacks of the earlier methods. In MDHE, we have decomposed the input
sixty-four parts, applied CHE in each of the sub-images and then finally
interpolated them in correct order. The final image after MDHE results in
contrast enhanced and brightness preserved image compared to all other
techniques mentioned above. We have calculated the various parameters like
PSNR, SNR, RMSE, MSE, etc. for every technique. Our results are well supported
by bar graphs, histograms and the parameter calculations at the end.


title: Quark matter in Neutron Stars within the Field Correlator Method

abstract:
  We discuss the appearance of quark matter in neutron star cores', focussing
on the possibility that the recent observation of a very heavy neutron star
could constrain free parameters of quark matter models. For that, we use the
equation of state derived with the Field Correlator Method, extended to the
zero temperature limit, whereas for the hadronic phase we use the equation of
state obtained within both the non-relativistic and the relativistic
Brueckner-Hartree-Fock many-body theory. We find a strong dependence of the
maximum mass both on the value of the q\bar q interaction V_1, and on the gluon
condensate G_2, for which we introduce a dependence on the baryon chemical
potential mu_B. We find that the maximum masses are consistent with the
observational limit for not too small values of V_1.


title: Impact of E-ELT laser light on Cherenkov Telescope Array cameras

abstract:
  As one of the options, the Cherenkov Telescope Array (CTA) Consortium is
considering the possibility to install its Southern array in Chile, in the
Atacama Desert. The envisaged site is situated about 5 km from the future
European Extremely Large Telescope (E-ELT), which will operate 8 parallel DC
lasers emitting at 589.2 nm, to create an artificial 6.8 magnitude star at an
altitude of 90 km. The guide stars are used for the adaptive optics of the
telescope. Although having the artificial stars in the field-of-view of a CTA
telescope would happen rather seldom, and can be avoided by coordinated
scheduling, the laser beams may cross the field-of-view of a telescope more
frequently and leave spurious light tracks, hence complicating the analysis of
the shower images. We derive an approximate formula to estimate the expected
number of photons from molecular and aerosol scattering of the laser light beam
into the field-of-view of a camera pixel. We then present several specific
cases of laser influence on the CTA camera pixels, based on the selected
direction of the laser beam, using the expected quantum efficiency of the
camera photomultipliers at the given wavelength.


title: Chaotic Variations of AES Algorithm

abstract:
  Advanced Encryption Standard (AES) algorithm is considered as a secured
algorithm. Still, some security issues lie in the S-Box and the key used. In
this paper, we have tried to give focus on the security of the key used. Here,
the proposed modified algorithms for the AES have been simulated and tested
with different chaotic variations such as 1-D logistic chaos equation, cross
chaos equation as well as combination of both. For the evaluation purpose, the
CPU time has been taken as the parameter. Though the variations of AES
algorithms are taking some more time as compared to the standard AES algorithm,
still the variations can be taken into consideration in case of more sensitive
information. As we are giving more security to the key used for AES algorithm,
our proposed algorithms are very much secured from unauthorized people.


title:
PVC composite internal process of current-voltage time delay formation
  and conductivity levels lifetimes origin

abstract:
  In the previously described model of interpreting the numerous results in the
switching states of the conduction in the films of PVC composites [1,2] was
noted the need to involve hopping mechanism and percolation theory to explain
the phenomenon of giant jumps conductivity, just as was done for the
interpretation of such jumps for disordered semiconductor films. It was also
shown that to explain the totality of spontaneous and stimulated transitions
between states of the conduction in PVC composites requires the existence of an
internal process that is able to produce a fixed observable current - voltage
delay and switching electrical conductivity levels lifetime. In this paper one
of the possible relaxation processes that lead to the emergence of the delay
time, and the occurrence of spontaneous and stimulated transitions sample
conductivity of nanocomposites PVC is presented. In particular, as a mechanism
for determining time delay and lifetimes of the conduction states the reaction
of dehydrochlorination is proposed, which should be reversible in case when HCl
molecules separated from macromolecule physically can not "travel" far from
"their place" in the macromolecule, as it just takes place within a local PVC
free volume. In a frame of developed model all previously observed and called
"anomalous" electrical phenomena receive a reasonable and predictable behavior.


title: Internal Motion of 6.7-GHz Methanol Masers in H II Region S269

abstract:
  We present the first internal motion measurement of the 6.7-GHz methanol
maser within S269, a small HII region in the outer Galaxy, which was carried
out in 2006 and 2011 using the Japanese VLBI Network (JVN). Several maser
groups and weak isolated spots were detected in an area spanning by ~200 mas
(1000 AU). Three remarkable maser groups are aligned at a position angle of 80
degree. Two of three maser groups were also detected by a previous observation
in 1998, which allowed us to study a long-term position variation of maser
spots from 1998 to 2011. The angular separation between the two groups
increased ~10 mas, which corresponds to an expansion velocity of ~10 km s^{-1}.
Some velocity gradient (~10^{-2} km s^{-1} mas^{-1}) in the overall
distribution was found. The internal motion between the maser groups support
the hypothesis that the methanol masers in S269 could trace a bipolar outflow.


title:
Measuring capital market efficiency: Long-term memory, fractal dimension
  and approximate entropy

abstract:
  We utilize long-term memory, fractal dimension and approximate entropy as
input variables for the Efficiency Index [Kristoufek & Vosvrda (2013), Physica
A 392]. This way, we are able to comment on stock market efficiency after
controlling for different types of inefficiencies. Applying the methodology on
38 stock market indices across the world, we find that the most efficient
markets are situated in the Eurozone (the Netherlands, France and Germany) and
the least efficient ones in the Latin America (Venezuela and Chile).


title:
The technology of using a data warehouse to support decision-making in
  health care

abstract:
  This paper describes the technology of data warehouse in healthcare
decision-making and tools for support of these technologies, which is used to
cancer diseases. The healthcare executive managers and doctors needs
information about and insight into the existing health data, so as to make
decision more efficiently without interrupting the daily work of an On-Line
Transaction Processing (OLTP) system. This is a complex problem during the
healthcare decision-making process. To solve this problem, the building a
healthcare data warehouse seems to be efficient. First in this paper we explain
the concepts of the data warehouse, On-Line Analysis Processing (OLAP).
Changing the data in the data warehouse into a multidimensional data cube is
then shown. Finally, an application example is given to illustrate the use of
the healthcare data warehouse specific to cancer diseases developed in this
study. The executive managers and doctors can view data from more than one
perspective with reduced query time, thus making decisions faster and more
comprehensive.


title: Higher-order frobenius-Euler and poly-Bernoulli mixed type polynomials

abstract:
  In this paper, we consider higher-order Frobenius-Euler polynomi- als
associated with poly-Bernoulli polynomials which are derived from
polylogarithmic function. These polynomials are called higher-order
Frobenius-Euler and poly-Bernoulli mixed type polynomials. The purpose of this
paper is to give various identities of those polynomials arising from umbral
calculus.


title: Solitons on tori and soliton crystals

abstract:
  Necessary conditions for a soliton on a torus $M=\R^m/\Lambda$ to be a
soliton crystal, that is, a spatially periodic array of topological solitons in
stable equilibrium, are derived. The stress tensor of the soliton must be $L^2$
orthogonal to $\ee$, the space of parallel symmetric bilinear forms on $TM$,
and, further, a certain symmetric bilinear form on $\ee$, called the hessian,
must be positive. It is shown that, for baby Skyrme models, the first condition
actually implies the second. It is also shown that, for any choice of period
lattice $\Lambda$, there is a baby Skyrme model which supports a soliton
crystal of periodicity $\Lambda$. For the three-dimensional Skyrme model, it is
shown that any soliton solution on a cubic lattice which satisfies a virial
constraint and is equivariant with respect to (a subgroup of) the lattice
symmetries automatically satisfies both tests. This verifies in particular that
the celebrated Skyrme crystal of Castillejo {\it et al.}, and Kugler and
Shtrikman, passes both tests.


title: Black Holes in Supergravity with Applications to String Theory

abstract:
  This thesis is devoted to the study of black hole solutions in ungauged
four-dimensional extended Supergravity. We characterize the most general
spherically symmetric and static black-hole solution of ungauged Supergravity,
and use the result to study the hidden conformal symmetries of Supergravity
black holes, obtaining the full Virasoro algebra of the dual conformal field
theory. We obtain also all the supersymmetric black-hole metrics of all
extended Supergravities using the properties of the groups of Type E7. We
introduce the H-F.G.K. formalism, which simplifies the construction of
non-supersymmetric black-hole solutions in N=2 Supergravity, and apply it to a
class of theories corresponding to Type-IIA String Theory compactified on a
Calabi-Yau threefold. As a result we obtain the so-called "quantum" black
holes, which only exist when certain quantum corrections (perturbative or
non-perturbative, depending on the solution) are included in the prepotential.
For the case of non-perturbative black holes, we elaborate on the potential
consequences of the appearance on the solution of multi-valued functions in
relation to the no-hair theorem for four-dimensional black holes. This thesis
also contains the relevant mathematical background to formulate extended
ungauged Supergravity in four-dimensions, that is, Special K\"ahler Geometry
and homogeneous spaces, as well as a brief introduction to the mathematical
structure of four-dimensional extended ungauged Supergravity.


title: Comment on "Effective thermal conductivity in thermoelectric materials"

abstract:
  In a recent article, Baranowski et al. [J. Appl. Phys. 113, 204904 (2013)]
proposed a model that allegedly facilitates optimization of thermoelectric
generators operation as these latter are in contact with hot and cold
temperature baths through finite conductance heat exchangers. In this Comment,
we argue that the results and analyses presented by these authors are
misleading since their model is incomplete and rests on an inappropriate
assumption derived from thermoelectric compatibility theory.


title: Chow Rings of Fine Quiver Moduli are Tautologically Presented

abstract:
  A result of A. King and C. Walter asserts that the Chow ring of a fine quiver
moduli space is generated by the Chern classes of universal bundles if the
quiver is acyclic. We will show that defining relations between these Chern
classes arise geometrically as degeneracy loci associated to the universal
representation.


title:
Non-LTE models for synthetic spectra of type Ia supernovae. III. An
  accelerated lambda iteration procedure for the mutual interaction of strong
  spectral lines in SN Ia models with and without energy deposition

abstract:
  Context. Spectroscopic analyses to interpret the spectra of the brightest
supernovae from the UV to the near-IR provide a powerful tool with great
astrophysical potential for the determination of the physical state of the
ejecta, their chemical composition, and the SNe distances even at significant
redshifts.
  Methods. We report on improvements of computing synthetic spectra for SNIa
with respect to i) an improved and sophisticated treatment of thousands of
strong lines that interact intricately with the "pseudo-continuum" formed
entirely by Doppler- shifted spectral lines, ii) an improved and expanded
atomic database, and iii) the inclusion of energy deposition within the ejecta.
  Results. We show that an accelerated lambda iteration procedure we have
developed for the mutual interaction of strong spectral lines appearing in the
atmospheres of SNeIa solves the longstanding problem of transferring the
radiative energy from the UV into the optical regime. In detail we discuss
applications of the diagnostic technique by example of a standard SNIa, where
the comparison of calculated and observed spectra revealed that in the early
phases the consideration of the energy deposition within the spectrum-forming
regions of the ejecta does not qualitatively alter the shape of the spectra.
  Conclusions. The results of our investigation lead to an improved
understanding of how the shape of the spectrum changes radically as function of
depth in the ejecta, and show how different emergent spectra are formed as a
result of the particular physical properties of SNe Ia ejecta and the resulting
peculiarities in the radiative transfer. This provides an important insight
into the process of extracting information from observed SNIa spectra, since
these spectra are a complex product of numerous unobservable SNIa spectral
features which are thus analyzed in parallel to the observable spectral
features.


title:
On the global existence of generalized rotational hypersurfaces with
  prescribed mean curvature in the Euclidean spaces. I

abstract:
  We prove that any piece of a rotational hypersurface with prescribed mean
curvature function in a Euclidean space can be uniquely extended infinitely,
which generalizes the results by Euler and Delaunay for surfaces of revolution
with constant mean curvautre. Next, we prove the same kind of theorem for
generalized rotational hypersurfaces of O(l+1) x O(m+1)-type. The key lemmas in
this paper show the existence of solutions for singular initial value problems
which arise from the analysis of ordinary differential equations of generating
curves of those hypersurfaces.


title: On third homology of SL_2 and weak homotopy invariance

abstract:
  The goal of the paper is to achieve - in the special case of the linear group
SL_2 - some understanding of the relation between group homology and its
A^1-invariant replacement. We discuss some of the general properties of
A^1-invariant group homology, such as stabilization sequences and
Grothendieck-Witt module structures. Together with very precise knowledge about
refined Bloch groups, these methods allow to deduce that in general there is a
rather large difference between group homology and its A^1-invariant version.
In other words, weak homotopy invariance fails for SL_2 over many families of
non-algebraically closed fields.


title: Optimal probabilistic measurement of phase

abstract:
  When measuring phase of quantum states of light, the optimal single-shot
measurement implements projection on the un-physical phase states. If we want
to improve the precision further we need to accept a reduced probability of
success, either by implementing a probabilistic measurement or by
probabilistically manipulating the measured quantum state by means of noiseless
amplification. We analyze the limits of this approach by finding the optimal
probabilistic measurement which, for a given rate of success, maximizes the
precision with which the phase can be measured.


title:
A short circuit in the electrical cables with polymer insulation: a new
  look at the cause of its occurrence and non-traditional ways of solving the
  problem

abstract:
  It is known that most of the electrical cables use as insulation compositions
based on polyvinyl chloride. Like most polymers, the latter is quite sensitive
to thermal aging, which is not without reason, to be one of the main causes of
the various types of faults in the polymeric insulation, leading eventually to
a short circuit and fire. On the example of the most common polymer
insulator-PVC subjected to preliminary partial thermolysis, simulating the
process of accelerated aging, we for the first time show that in this case as a
result of the aging process, the electrical conductivity of PVC can acquire
abnormal (not obeying Ohm's law) character. In this case, transitions from a
state with normal (low) conductivity of PVC into the state with an ab-normally
high conductivity was clearly observed, being spontaneous uncontrollable
process. Es-pecially the large-scale nature of these changes allowing easily
transferring polyvinylchloride from a state of typical dielectric (insulator)
in a class of conductors attracts attention.). Thus, an-other one of the most
important features of a short circuit in the PVC insulation is opened. It is
noted that the reduction of fire hazards in this case (by the maximum possible
elimination of the phenomenon of short circuit due to thermal aging of
polymeric insulation) should be preventive in nature, as the most effective,
simple and convenient way.


title:
Polar Surface Effects on the Thermal Conductivity in ZnO Nanowires: a
  Shell-Like Surface Reconstruction-Induced Preserving Mechanism

abstract:
  We perform molecular dynamics (MD) simulations to investigate the effect of
polar surfaces on the thermal transport in zinc oxide (ZnO) nanowires. We find
that the thermal conductivity in nanowires with free polar (0001) surfaces is
much higher than in nanowires that have been stabilized with reduced charges on
the polar (0001) surfaces, and also hexagonal nanowires without any transverse
polar surfaces. From normal mode analysis, we show that the higher thermal
conductivity is due to a shell-like reconstruction that occurs for the free
polar surfaces. This shell-like reconstruction suppresses twisting motion in
the nanowires such that the bending phonon modes are not scattered by the other
phonon modes, and leads to substantially higher thermal conductivity in the ZnO
nanowire with free polar surfaces. Furthermore, the auto-correlation function
of the normal mode coordinate is utilized to extract the phonon lifetime, which
leads to a concise explanation for the higher thermal conductivity in ZnO
nanowires with free polar surfaces. Our work demonstrates that ZnO nanowires
without polar surfaces, which exhibit low thermal conductivity, are more
promising candidates for thermoelectric applications than nanowires with polar
surfaces (and also high thermal conductivity).


title: Finding small patterns in permutations in linear time

abstract:
  Given two permutations $\sigma$ and $\pi$, the \textsc{Permutation Pattern}
problem asks if $\sigma$ is a subpattern of $\pi$. We show that the problem can
be solved in time $2^{O(\ell^2\log \ell)}\cdot n$, where $\ell=|\sigma|$ and
$n=|\pi|$. In other words, the problem is fixed-parameter tractable
parameterized by the size of the subpattern to be found.
  We introduce a novel type of decompositions for permutations and a
corresponding width measure. We present a linear-time algorithm that either
finds $\sigma$ as a subpattern of $\pi$, or finds a decomposition of $\pi$
whose width is bounded by a function of $|\sigma|$. Then we show how to solve
the \textsc{Permutation Pattern} problem in linear time if a bounded-width
decomposition is given in the input.


title: Realizing optical pulling force using chirality

abstract:
  We derived an analytical formula for the optical force acting on a small
anisotropic chiral particle. The behavior of chiral particles is qualitatively
different from achiral particles due to new chirality dependent terms which
couple mechanical linear momentum and optical spin angular momentum. Such
coupling induced by chirality can serve as a new mechanism to achieve optical
pulling force. Our analytical predictions are verified by numerical
simulations.


title: Low Power Dual Edge-Triggered Static D Flip-Flop

abstract:
  This paper enumerates new architecture of low power dual-edge triggered
Flip-Flop (DETFF) designed at 180nm CMOS technology. In DETFF same data
throughput can be achieved with half of the clock frequency as compared to
single edge triggered Flip-Flop (SETFF). In this paper conventional and
proposed DETFF are presented and compared at same simulation conditions. The
post layout experimental results comparison shows that the average power
dissipation is improved by 48.17%, 41.29% and 36.84% when compared with SCDFF,
DEPFF and SEDNIFF respectively and improvement in PDP is 42.44%, 33.88% and
24.69% as compared to SCDFF, DEPFF and SEDNIFF respectively. Therefore the
proposed DETFF design is suitable for low power and small area applications.


title: Interplay between folding and assembly of fibril-forming polypeptides

abstract:
  Polypeptides can self-assemble into hierarchically organized fibrils
consisting of a stack of individually folded polypeptides driven together by
hydrophobic interaction. Using a coarse grained model, we systematically
studied this self-assembly as a function of temperature and hydrophobicity of
the residues on the outside of the building block. We find the self-assembly
can occur via two different pathways - a random aggregation-folding route, and
a templated-folding process - thus indicating a strong coupling between folding
and assembly. The simulation results can explain experimental evidence that
assembly through stacking of folded building blocks is rarely observed, at the
experimental concentrations. The model thus provides a generic picture of
hierarchical fibril formation.


title:
Asymptotically AdS Charged Black Holes in String Theory with
  Gauss-Bonnet Correction in Various Dimensions

abstract:
  We study charged black hole solutions in Einstein-Maxwell-Gauss-Bonnet theory
with the dilaton field which is the low-energy effective theory of the
heterotic string. The spacetime is $D$-dimensional and assumed to be static and
plane symmetric with the $(D-2)$-dimensional constant curvature space and
asymptotically anti-de Sitter. By imposing the boundary conditions of the
existence of the regular black hole horizon and proper behavior at infinity
where the Breitenlohner-Freedman bound should be satisfied, we construct black
hole solutions numerically. We give the relations among the physical quantities
of the black holes such as the horizon radius, the mass, the temperature, and
so on. The properties of the black hole do not depend on the dimensions
qualitatively, which is different from the spherically symmetric and
asymptotically flat case. There is non-zero lower limit for the radius of the
event horizon below which no solution exists. The temperature of the black hole
becomes smaller as the horizon radius is smaller but remains non-zero when the
lower limit is attained.


title:
Quantum-field-theoretical approach to phase-space techniques: Symmetric
  Wick theorem and multitime Wigner representation

abstract:
  In this work we present the formal background used to develop the methods
used in earlier works to extend the truncated Wigner representation of quantum
and atom optics in order to address multi-time problems. The truncated Wigner
representation has proven to be of great practical use, especially in the
numerical study of the quantum dynamics of Bose condensed gases. In these
cases, it allows for the simulation of effects which are missed entirely by
other approximations, such as the Gross-Pitaevskii equation, but does not
suffer from the severe instabilities of more exact methods. The numerical
treatment of interacting many-body quantum systems is an extremely difficult
task, and the ability to extend the truncated Wigner beyond single-time
situations adds another powerful technique to the available toolbox. This
article gives the formal mathematics behind the development of our "time-Wigner
ordering" which allows for the calculation of the multi-time averages which are
required for such quantities as the Glauber correlation functions which are
applicable to bosonic fields.

categories: quant-ph cond-mat.quant-gas cond-mat.soft math-ph math.MP


title: Observation of particle pairing in a two-dimensional plasma crystal

abstract:
  The observation is presented of naturally occurring pairing of particles and
their cooperative drift in a two-dimensional plasma crystal. A single layer of
plastic microspheres was suspended in the plasma sheath of a capacitively
coupled rf discharge in argon at a low pressure of 1 Pa. The particle dynamics
were studied by combining the top-view and side-view imaging of the suspension.
Cross analysis of the particle trajectories allowed us to identify naturally
occurring metastable pairs of particles. The lifetime of pairs was long enough
for their reliable identification.


title:
Optimal competitiveness for Symmetric Rectilinear Steiner Arborescence
  and related problems

abstract:
  We present optimal competitive algorithms for two interrelated known problems
involving Steiner Arborescence. One is the continuous problem of the Symmetric
Rectilinear Steiner Arborescence (SRSA), studied by Berman and Coulston.
  A very related, but discrete problem (studied separately in the past) is the
online Multimedia Content Delivery (MCD) problem on line networks, presented
originally by Papadimitriu, Ramanathan, and Rangan. An efficient content
delivery was modeled as a low cost Steiner arborescence in a grid of
network*time they defined. We study here the version studied by Charikar,
Halperin, and Motwani (who used the same problem definitions, but removed some
constraints on the inputs).
  The bounds on the competitive ratios introduced separately in the above
papers are similar for the two problems: O(log N) for the continuous problem
and O(log n) for the network problem, where N was the number of terminals to
serve, and n was the size of the network. The lower bounds were Omega(sqrt{log
N}) and Omega(sqrt{log n}) correspondingly. Berman and Coulston conjectured
that both the upper bound and the lower bound could be improved.
  We disprove this conjecture and close these quadratic gaps for both problems.
We first present an O(sqrt{log n}) deterministic competitive algorithm for MCD
on the line, matching the lower bound. We then translate this algorithm to
become a competitive optimal algorithm O(sqrt{log N}) for SRSA. Finally, we
translate the latter back to solve MCD problem, this time competitive optimally
even in the case that the number of requests is small (that is, O(min{sqrt{log
n},sqrt{log N}})). We also present a Omega(sqrt[3]{log n}) lower bound on the
competitiveness of any randomized algorithm. Some of the techniques may be
useful in other contexts.


title: Hartree-Fock Ground State Phase Diagram of Jellium

abstract:
  We calculate the ground state phase diagram of the homogeneous electron gas
in three dimensions within the Hartree-Fock approximation and show that broken
symmetry states are energetically favored at any density against the
homogeneous Fermi gas state with isotropic Fermi surface. At high density, we
find metallic spin-unpolarized solutions where electronic charge and spin
density form an incommensurate crystal having more crystal sites than
electrons. For $r_s \to 0$, our solutions approach pure spin-density waves,
whereas the commensurate Wigner crystal is favored at lower densities, $r_s >
3.4$. Decreasing the density, the system undergoes several structural phase
transitions with different lattice symmetries. The polarization transition
occurs around $r_s \approx 8.5$.


title:
On the global existence of generalized rotational hypersurfaces with
  prescribed mean curvature in the Euclidean spaces, II

abstract:
  In the previous paper, it has been proved that the generalized rotational
hypersurfaces of O(n-1)-type and O (l+1) x O(m+1)-type, for which the mean
curvature is any prescribed continuous function. This paper is a sequel, and a
similar existence result is shown for any type.


title:
A photometric study of the nova-like variable TT Arietis with the MOST
  satellite

abstract:
  Variability on all time scales between seconds and decades is typical for
cataclysmic variables (CVs). One of the brightest and best studied CVs is TT
Ari, a nova-like variable which belongs to the VY Scl subclass, characterized
by occasional low states in their light curves. It is also known as a permanent
superhumper at high state, revealing "positive" (P_S > P_0) as well as
"negative" (P_S < P_0) superhumps, where P_S is the period of the superhump and
P_0 the orbital period. TT Ari was observed by the Canadian space telescope
MOST for about 230 hours nearly continuously in 2007, with a time resolution of
48 seconds. Here we analyze these data, obtaining a dominant "negative"
superhump signal with a period P_S = 0.1331 days and a mean amplitude of 0.09
mag. Strong flickering with amplitudes up to 0.2 mag and peak-to-peak time
scales of 15-20 minutes is superimposed on the periodic variations. We found no
indications for significant quasi-periodic oscillations with periods around 15
minutes, reported by other authors. We discuss the known superhump behaviour of
TT Ari during the last five decades and conclude that our period value is at
the upper limit of all hitherto determined "negative" superhump periods of TT
Ari, before and after the MOST run.


title: The travel time in a finite box in supercritical Bernoulli percolation

abstract:
  We consider the standard site percolation model on the three dimensional
cubic lattice. Starting solely with the hypothesis that $\theta(p)>0$, we prove
that, for any $\alpha>0$, there exists $\kappa>0$ such that, with probability
larger than $1-1/n^\alpha$, every pair of vertices inside the box $\Lambda(n)$
are joined by a path having at most $\kappa(\ln n)^2$ closed sites.


title:
The static quark potential from the gauge invariant Abelian
  decomposition

abstract:
  We investigate the relationship between colour confinement and topological
structures derived from the gauge invariant Abelian (Cho-Duan-Ge)
decomposition. This Abelian decomposition is made imposing an isometry on a
colour field $n$ which selects the Abelian direction; the principle novelty of
our study is that we have defined this field in terms of the eigenvectors of
the Wilson Loop. This allows us to establish an equivalence between the path
ordered integral of the non-Abelian gauge fields with an integral over an
Abelian restricted gauge field which is tractable both theoretically and
numerically in lattice QCD. By using Stokes' theorem, we can relate the Wilson
Loop in terms of a surface integral over a restricted field strength, and show
that the restricted field strength may be dominated by topological structures,
which occur when one of the parameters parametrising the colour field $n$ winds
itself around a non-analyticity in the colour field. If they exist, these
objects will lead to an area law scaling for the Wilson Loop and provide a
mechanism for quark confinement. We search for these structures in quenched
lattice QCD. We perform the Abelian decomposition, and find that the restricted
field strength is dominated by peaks on the lattice. Wilson Loops containing
these peaks show a stronger area-Law and thus provide the dominant contribution
to the string tension.


title: Towards a Good ABS Design for more Reliable Vehicles on the Roads

abstract:
  Nowadays, better driving also means better braking. To this end, vehicle
designers must find all failures during the design phase of antilock braking
systems which play an important role in automobiles safety. However,
mechatronic systems are so complex and failures can be badly identified. So it
is necessary to propose a design approach of an antilock braking system which
will be able to avoid wheels locking during braking and maintain vehicle
stability. This paper describes this approach, in which we model the functional
and the dysfunctional behavior of an antilock braking system using stopwatch
Petri nets.


title: Parametrix construction for certain L\'evy-type processes

abstract:
  In this paper we show that a non-local operator of certain type extends to
the generator of a strong Markov process, admitting the transition probability
density. For this transition probability density we construct the intrinsic
upper and lower bounds, and prove some smoothness properties.
  Some examples are provided.


title:
The Declaratron, semantic specification for scientific computation using
  MathML

abstract:
  We introduce the Declaratron, a system which takes a declarative approach to
specifying mathematically based scientific computation. This uses displayable
mathematical notation (Content MathML) and is both executable and semantically
well defined. We combine domain specific representations of physical science
(e.g. CML, Chemical Markup Language), MathML formulae and computational
specifications (DeXML) to create executable documents which include scientific
data and mathematical formulae. These documents preserve the provenance of the
data used, and build tight semantic links between components of mathematical
formulae and domain objects---in effect grounding the mathematical semantics in
the scientific domain. The Declaratron takes these specifications and i)
carries out entity resolution and decoration to prepare for computation ii)
uses a MathML execution engine to run calculations over the revised tree iii)
outputs domain objects and the complete document to give both results and an
encapsulated history of the computation. A short description of a case study is
given to illustrate how the system can be used. Many scientific problems
require frequent change of the mathematical functional form and the Declaratron
provides this without requiring changes to code. Additionally, it supports
reproducible science, machine indexing and semantic search of computations,
makes implicit assumptions visible, and separates domain knowledge from
computational techniques. We believe that the Declaratron could replace much
conventional procedural code in science.


title:
Causal signal transmission by quantum fields -- V: Generalised Keldysh
  rotations and electromagnetic response of the Dirac sea

abstract:
  The connection between real-time quantum field theory (RTQFT) [see, e.g., A.\
Kamenev and A.\ Levchenko, Advances in Physics {58} (2009) 197] and phase-space
techniques [E.\ Wolf and L.\ Mandel, {\em Optical Coherence and Quantum Optics}
(Cambridge, 1995)] is investigated. The Keldysh rotation that forms the basis
of RTQFT is shown to be a phase-space mapping of the quantum system based on
the symmetric (Weyl) ordering. Following this observation, we define
generalised Keldysh rotations based on the class of operator orderings
introduced by Cahill and Glauber [Phys.\ Rev.\ {177} (1969) 1882]. Each
rotation is a phase-space mapping, generalising the corresponding ordering from
free to interacting fields. In particular, response transformation [L.P.\ and
S.S., Ann.\ Phys. (N.Y.) {323} (2008) 1989] extends the normal ordering of
free-field operators to the time-normal ordering of Heisenberg\ operators.
Structural properties of the response transformation, such as its association
with the nonlinear quantum response problem and the related causality
properties, hold for all generalised Keldysh rotations.
  Furthermore, we argue that response transformation is especially suited for
RTQFT formulation of spatial, in particular, relativistic, problems, because it
extends cancellation of zero-point fluctuations, characteristic of the normal
ordering, to interacting fields. As an example, we consider quantised
electromagnetic\ field in the Dirac sea. In the time-normally-ordered
representation, dynamics of the field looks essentially classical (fields
radiated by currents), without any contribution from zero-point fluctuations.
For comparison, we calculate zero-point fluctuations of the interacting
electromagnetic\ field under orderings other than time-normal. The resulting
expression is physically inconsistent: it does not obey the Lorentz condition,
nor Maxwell's equations.


title: Impedance spectroscopy of ions at liquid-liquid interfaces

abstract:
  The possibility to extract properties of an interface between two immiscible
liquids, e.g., electrolyte solutions or polyelectrolyte multilayers, by means
of impedance spectroscopy is investigated theoretically within a dynamic
density functional theory which is equivalent to the Nernst-Planck-Poisson
theory. A novel approach based on a two-step fitting procedure of an equivalent
circuit to impedance spectra is proposed which allows to uniquely separate bulk
and interfacial elements. Moreover, the proposed method avoids overfitting of
the bulk properties of the two liquids in contact and underfitting of the
interfacial properties, as they might occur for standard one-step procedures.
The key idea is to determine the bulk elements of the equivalent circuit in a
first step by fitting corresponding sub-circuits to the spectra of uniform
electrolyte solutions, and afterwards fitting the full equivalent circuit with
fixed bulk elements to the impedance spectrum containing the interface. This
approach is exemplified for an equivalent circuit which leads to a physically
intuitive qualitative behavior as well as to quantitively realistic values of
the interfacial elements. The proposed method is robust such that it can be
expected to be applicable to a wide class of systems with liquid-liquid
interfaces.


title: Artificial Intelligence MArkup Language: A Brief Tutorial

abstract:
  The purpose of this paper is to serve as a reference guide for the
development of chatterbots implemented with the AIML language. In order to
achieve this, the main concepts in Pattern Recognition area are described
because the AIML uses such theoretical framework in their syntactic and
semantic structures. After that, AIML language is described and each AIML
command/tag is followed by an application example. Also, the usage of AIML
embedded tags for the handling of sequence dialogue limitations between humans
and machines is shown. Finally, computer systems that assist in the design of
chatterbots with the AIML language are classified and described.


title:
Determination of matter potential from global analysis of neutrino
  oscillation data

abstract:
  We quantify our current knowledge of the size and flavor structure of the
matter effects in the evolution of neutrinos based solely on the global
analysis of oscillation neutrino data. The results are translated in terms of
the present allowed ranges for the corresponding non-standard neutrino
interactions in matter.


title: Dynamical F-strings intersecting D2-branes in type IIA supergravity

abstract:
  We present time-dependent exact solutions composed of F-strings intersecting
D2-branes in type IIA supergravity. The F-strings tend to approach each other
with time in the six-dimensional space transverse to both F-strings and
D2-branes. In general, a singularity appears before collision. An exceptional
case is that the charges are the same and five directions in the transverse
space are smeared out. Then we argue some applications of the solutions in
building cosmological models. The possible models are classified based on
compactifications of the internal space. All of them give rise to the
Friedmann-Robertson-Walker universe with a power-law expansion.


title: Structures of the Planets Jupiter and Saturn

abstract:
  New equations of state (EOS) for hydrogen, helium, and compounds containing
heavier elements are used to construct models for the structures of the planets
Jupiter and Saturn. Good agreement with the gravitational moments J2 and J4 is
obtained with a model that uses a two-layer gas envelope, in which the inner
region is denser than the outer one, together with a small, dense core. It is
possible to match J2 with a homogeneous envelope, but an envelope with a denser
inner region is needed to match both moments. The two-layer envelope also gives
good agreement with the global oscillation data for Jupiter. In Jupiter, the
boundary between the inner and outer envelopes occurs at 319 GPa, with an 8%
density increase. In Saturn, it occurs at 227 GPa, with a 69% density increase.
The differences between the two planets show that the need for a density
increase is not due to EOS errors. It is also shown that helium enrichment
cannot be the cause of the density increase. The phenomenon can be explained as
the result of enrichment of heavy elements from planetismals that were
dispersed and mixed with the gases during planet formation. This conclusion is
consistent with planetary formation models like that of Pollack, et al.


title:
Fundamental Limits of Energy-Efficient Resource Sharing, Power Control
  and Discontinuous Transmission

abstract:
  The achievable gains via power-optimal scheduling are investigated. Under the
QoS constraint of a guaranteed link rate, the overall power consumed by a
cellular BS is minimized. Available alternatives for the minimization of
transmit power consumption are presented. The transmit power is derived for the
two-user downlink situation. The analysis is extended to incorporate a BS power
model (which maps transmit power to supply power consumption) and the use of
DTX in a BS. Overall potential gains are evaluated by comparison of a
conventional SOTA BS with one that employs DTX exclusively, a power control
scheme and an optimal combined DTX and power control scheme. Fundamental limits
of the achievable savings are found to be at 5.5 dB under low load and 2 dB
under high load when comparing the SOTA consumption with optimal allocation
under the chosen power model.


title:
Electro-Thermo-Chemical Computational Models for 3D Heterogeneous
  Semiconductor Device Simulation

abstract:
  In this article we propose and numerically implement a mathematical model for
the simulation of three-dimensional semiconductor devices characterized by an
heterogeneous material structure. The model consists of a system of nonlinearly
coupled time-dependent diffusion-reaction partial differential equations with
convection terms describing the principal electrical, thermal and chemical
phenomena that determine the macroscopic electrical response of the device
under the action of externally applied electrical and thermal forces. The
system is supplied with suitable initial, boundary and interface conditions
that account for the interaction occurring among the various regions of the
device with the surrounding environment. Temporal semi-discretization of the
problem is carried out with the Backward Euler Method while a fixed-point
iteration of Gummel type is used for system decoupling. Numerical approximation
of the linearized subproblems is carried out using an exponentially fitted
stabilized Finite Element Method on unstructured tetrahedral grids. Several
computational experiments are included to validate the physical accuracy of the
proposed computational algorithm in the study of realistic device structures.


title: Extinction in four species cyclic competition

abstract:
  When four species compete stochastically in a cyclic way, the formation of
two teams of mutually neutral partners is observed. In this paper we study
through numerical simulations the extinction processes that can take place in
this system both in the well mixed case as well as on different types of
lattices. The different routes to extinction are revealed by the probability
distribution of the domination time, i.e. the time needed for one team to fully
occupy the system. If swapping is allowed between neutral partners, then the
probability distribution is dominated by very long-lived states where a few
very large domains persist, each domain being occupied by a mix of individuals
from species that form one of the teams. Many aspects of the possible
extinction scenarios are lost when only considering averaged quantities as for
example the mean domination time.


title:
Quarkonium measurements in Pb-Pb and p-Pb collisions with ALICE at the
  LHC

abstract:
  The ALICE experiment has measured quarkonium production in Pb-Pb collisions
at \sqrt{sNN} = 2.76 TeV and in p-Pb collisions at \sqrt{sNN} = 5.02 TeV. The
measurements are performed in the dielectron de- cay channel at mid-rapidity
(|yLAB| < 0.9) and in the dimuon decay channel at forward rapidity (2.5 < yLAB
< 4). We focus in particular on the J/{\psi} nuclear modification factor
measured both in Pb-Pb and p- -Pb collisions and on the {\Upsilon}(1S) nuclear
modification factor measured in Pb-Pb collisions.


title: Minimal average consumption downlink base station power control strategy

abstract:
  We consider single cell multi-user OFDMA downlink resource allocation on a
flat-fading channel such that average supply power is minimized while
fulfilling a set of target rates. Available degrees of freedom are transmission
power and duration. This paper extends our previous work on power optimal
resource allocation in the mobile downlink by detailing the optimal power
control strategy investigation and extracting fundamental characteristics of
power optimal operation in cellular downlink. We find that only a system wide
allocation of transmit powers is optimal rather than on link level. The
allocation strategy that minimizes overall power consumption requires the
transmission power on all links to be increased if only one link degrades.
Furthermore, we show that for mobile stations with equal channels but different
rate requirements, it is power optimal to assign equal transmit powers with
proportional transmit durations. To relate the effectiveness of power control
to live operation, we take the power model into consideration which maps
transmit power to supply power. We show that due to the affine mapping, the
solution is independent of the power model. However, the effectiveness of power
control measures is completely dependent on the underlying hardware and the
load dependence factor of a base station (instead of absolute consumption
values). Finally, we conclude that power control measures in base stations are
most relevant in macro stations which have load dependence factor of more than
50%.


title:
An Electron Bunch Compressor Based on an FEL Interaction in the Far
  Infra Red

abstract:
  In this note an electron bunch compressor is proposed based on FEL type
interaction of the electron bunch with far infrared (FIR) radiation. This
mechanism maintains phase space density and thus requires a high quality
electron beam to produce bunches of the length of a few ten micrometer.


title:
Analysis of the semileptonic $\Lambda_b\rightarrow \Lambda \ell^+
  \ell^-$ transition in topcolor-assisted technicolor (TC2) model

abstract:
  We comparatively analyze the flavor changing neutral current process of the
$\Lambda_b \rightarrow \Lambda \ell^+ \ell^-$ in the standard model as well as
topcolor-assisted technicolor model using the form factors calculated via light
cone QCD sum rules in full theory. In particular, we calculate the decay width,
branching ratio and lepton forward-backward asymmetry related to this decay
channel. We compare the results of the topcolor-assisted technicolor model with
those of the standard model and debate how the results of the topcolor-assisted
technicolor model depart from the standard model predictions. We also compare
our results on the differential branching ratio with recent experimental data
provided by CDF and LHCb Collaborations.


title:
Statistical Active Learning Algorithms for Noise Tolerance and
  Differential Privacy

abstract:
  We describe a framework for designing efficient active learning algorithms
that are tolerant to random classification noise and are
differentially-private. The framework is based on active learning algorithms
that are statistical in the sense that they rely on estimates of expectations
of functions of filtered random examples. It builds on the powerful statistical
query framework of Kearns (1993).
  We show that any efficient active statistical learning algorithm can be
automatically converted to an efficient active learning algorithm which is
tolerant to random classification noise as well as other forms of
"uncorrelated" noise. The complexity of the resulting algorithms has
information-theoretically optimal quadratic dependence on $1/(1-2\eta)$, where
$\eta$ is the noise rate.
  We show that commonly studied concept classes including thresholds,
rectangles, and linear separators can be efficiently actively learned in our
framework. These results combined with our generic conversion lead to the first
computationally-efficient algorithms for actively learning some of these
concept classes in the presence of random classification noise that provide
exponential improvement in the dependence on the error $\epsilon$ over their
passive counterparts. In addition, we show that our algorithms can be
automatically converted to efficient active differentially-private algorithms.
This leads to the first differentially-private active learning algorithms with
exponential label savings over the passive case.


title: On Minimizing Base Station Power Consumption

abstract:
  We consider resource allocation over a wireless downlink where Base Station
(BS) power consumption is minimized while upholding a set of required link
rates. A Power and Resource Allocation Including Sleep (PRAIS) method is
proposed that combines resource sharing, Power Control (PC), and Discontinuous
Transmission (DTX), such that downlink power consumption is minimized, which
can be formed into a convex optimization problem. Unlike conventional
approaches that aim at minimizing transmit power, in this work the BS mains
supply power is chosen as the relevant metric. Based on a linear power model,
which maps a certain transmit power to the necessary mains supply power, we
quantify the fundamental limits of PRAIS in terms of achievable BS power
savings. The fundamental limits are numerically evaluated on link level for
four sets of BS power model parameters representative of envisaged future
hardware developments. We establish an expected lower limit for PRAIS of 27W to
68W depending on load per link for BSs installed in 2014, which provides a 61%
to 34% gain over conventional resource allocation schemes.


title: The String Origin of SUSY Flavor Violation

abstract:
  We argue that in large classes of string compactifications with a MSSM-like
structure substantial flavor violating SUSY-breaking soft terms are generically
induced. We specify to the case of flavor dependent soft-terms in type
IIB/F-theory SU(5) unified models, although our results can be easily extended
to other settings. The Standard Model (SM) degrees of freedom reside in a local
system of 7-branes wrapping a 4-fold S in the extra dimensions. It is known
that in the presence of closed string 3-form fluxes SUSY-breaking terms are
typically generated. We explore the generation dependence of these soft terms
and find that non-universalities arise whenever the flux varies over the 4-fold
S. These non-universalities are parametrically suppressed by
(M_{GUT}/M_{Pl})^{1/3}. They also arise in the case of varying open string
fluxes, in this case parametrically suppressed by \alpha_{GUT}^{1/2}. For a
standard unification scheme with M_{GUT} = 10^{16} GeV and \alpha_{\rm GUT} =
1/24 these suppressions are very mild. Although limits from the kaon mass
difference \Delta m_K are easily obeyed for squark masses above the present LHC
limits, constraints from the CP-violation parameter \epsilon_K imply squark
masses in the multi-TeV region. The constraints from BR(\mu \rightarrow
e\gamma) turn out to be the strongest ones, with slepton masses of order ~10
TeV or heavier required to obey the experimental limits. These sfermion masses
are consistent with the observed large value m_H ~ 126 GeV of the Higgs mass.
We discuss under what conditions such strong limits may be relaxed allowing for
SUSY particle production at LHC.


title:
Non-LTE models for synthetic spectra of type Ia supernovae. IV. A
  modified Feautrier scheme for opacity-sampled pseudo-continua at high
  expansion velocities and application to synthetic SN Ia spectra

abstract:
  Context. Type Ia supernovae (SN Ia) have become an invaluable cosmological
tool as their exceptional brightness makes them observable even at very large
distances (up to redshifts around z~1). To investigate possible systematic
differences between local and distant SN Ia requires detailed models whose
synthetic spectra can be compared to observations, and in which the solution of
the radiative transfer is a key ingredient. One commonly employed method is the
Feautrier scheme, which is generally very robust, but which can yield wrong
results under certain conditions that frequently occur in the modelling of
supernova ejecta or even in the radiatively driven expanding atmospheres of hot
stars.
  Methods. We use a sophisticated model atmosphere code which takes into
account the non-LTE effects and high velocity gradients that strongly affect
the physics of SN Ia atmospheres at all wavelengths to simulate the formation
of SN Ia spectra by the thousands of strong spectral lines which intricately
interact with the "pseudo-continuum" formed entirely by these Doppler-shifted
lines themselves. We focus to an investigation of the behavior of the Feautrier
scheme under these conditions.
  Results. Synthetic spectra of SN Ia, a complex product of computer models
replicating numerous physical processes that determine the conditions of matter
and radiation in the ejecta, are affected by large spatial jumps of the
line-dominated opacities and source functions for which the application of even
well-established methods may harbor certain pitfalls. We analyze the conditions
that can lead to a breakdown of conventional procedures and we derive for the
Feautrier radiative transfer solver a modified description which yields more
accurate results in the given circumstances.


title:
Color-Kinematics Duality in Multi-Regge Kinematics and Dimensional
  Reduction

abstract:
  In this note we study the applicability of the color-kinematics duality to
the scattering of two distinguishable scalar matter particles with gluon
emission in QCD, or graviton emission in Einstein gravity. Previous analysis
suggested that direct use of the Bern-Carrasco-Johansson double-copy
prescription to matter amplitudes does not reproduce the gravitational
amplitude in multi-Regge kinematics. This situation, however, can be avoided by
extensions to the gauge theory, while maintaning the same Regge limit. Here we
present two examples of these extensions: the introduction of a scalar contact
interaction and the relaxation of the distinguishability of the scalars. In
both cases new diagrams allow for a full reconstruction of the correct Regge
limit on the gravitational side. Both modifications correspond to theories
obtained by dimensional reduction from higher-dimensional gauge theories.


title: An improvement of the Feng-Rao bound for primary codes

abstract:
  We present a new bound for the minimum distance of a general primary linear
code. For affine variety codes defined from generalised C_{ab} curves the new
bound often improves dramatically on the Feng-Rao bound for primary codes. The
method does not only work for the minimum distance but can be applied to any
generalised Hamming weight


title: Bernoulli, Ramanujan, Toeplitz and the triangular matrices

abstract:
  By using one of the definitions of the Bernoulli numbers, we prove that they
solve particular odd and even lower triangular Toeplitz (l.t.T.) systems of
equations. In a paper Ramanujan writes down a sparse lower triangular system
solved by Bernoulli numbers; we observe that such system is equivalent to a
sparse l.t.T. system. The attempt to obtain the sparse l.t.T. Ramanujan system
from the l.t.T. odd and even systems, has led us to study efficient methods for
solving generic l.t.T. systems. Such methods are here explained in detail in
case n, the number of equations, is a power of b, b=2,3 and b generic.


title: On complex power nonnegative matrices

abstract:
  Power nonnegative matrices are defined as complex matrices having at least
one nonnegative integer power. We exploit the possibility of deriving a Perron
Frobenius-like theory for these matrices, obtaining three main results and
drawing several consequences. We study, in particular, the relationships with
the set of matrices having eventually nonnegative powers, the inverse of M-type
matrices and the set of matrices whose columns (rows) sum up to one.


title: Minimizing Base Station Power Consumption

abstract:
  We propose a new radio resource management algorithm which aims at minimizing
the base station supply power consumption for multi-user MIMO-OFDM. Given a
base station power model that establishes a relation between the RF transmit
power and the supply power consumption, the algorithm optimizes the trade-off
between three basic power-saving mechanisms: antenna adaptation, power control
and discontinuous transmission. The algorithm comprises two steps: a) the first
step estimates sleep mode duration, resource shares and antenna configuration
based on average channel conditions and b) the second step exploits
instantaneous channel knowledge at the transmitter for frequency selective
time-variant channels. The proposed algorithm finds the number of transmit
antennas, the RF transmission power per resource unit and spatial channel, the
number of discontinuous transmission time slots, and the multi-user resource
allocation, such that supply power consumption is minimized. Simulation results
indicate that the proposed algorithm is capable of reducing the supply power
consumption by between 25% and 40%, dependend on the system load.


title: More constraining conformal bootstrap

abstract:
  Recently an efficient numerical method has been developed to implement the
constraints of crossing symmetry and unitarity on the operator dimensions and
OPE coefficients of conformal field theories (CFT) in diverse space-time
dimensions. It appears that the calculations can be done only for theories
lying at the boundary of the allowed parameter space. Here it is pointed out
that a similar method can be applied to a larger class of CFT's, whether
unitary or not, and no free parameter remains, provided we know the fusion
algebra of the low lying primary operators. As an example we calculate using
first principles, with no phenomenological input, the lowest scaling dimensions
of the local operators associated with the Yang-Lee edge singularity in three
and four space dimensions. The edge exponents compare favorably with the latest
numerical estimates. A consistency check of this approach on the 3d critical
Ising model is also made.


title: Vibrational energy transport in molecular wires

abstract:
  Motivated by recent experimental observation (see e.g., I.V.Rubtsov, Acc.
Chem. Res., v. 42, 1385 (2009)) of vibrational energy transport in CH_2O_N and
CF_2_N molecular chains (N = 4 - 12), in this paper we present and solve
analytically a simple one dimensional model to describe theoretically these
data. To mimic multiple conformations of the molecular chains, our model
includes random off-diagonal couplings between neighboring sites. For the sake
of simplicity we assume Gaussian distribution with dispersion sigma for these
coupling matrix elements. Within the model we find that initially locally
excited vibrational state can propagate along the chain. However the
propagation is neither ballistic nor diffusion like. The time T_m for the first
passage of the excitation along the chain, scales linearly with N in the
agreement with the experimental data. Distribution of the excitation energies
over the chain fragments (sites in the model) remains random, and the
vibrational energy, transported to the chain end at $t=T_m$ is dramatically
decreased when sigma is larger than characteristic interlevel spacing in the
chain vibrational spectrum. We do believe that the problem we have solved is
not only of intellectual interest (or to rationalize mentioned above
experimental data) but also of relevance to design optimal molecular wires
providing fast energy transport in various chemical and biological reactions.


title: Anarchy is free in network creation

abstract:
  The Internet has emerged as perhaps the most important network in modern
computing, but rather miraculously, it was created through the individual
actions of a multitude of agents rather than by a central planning authority.
This motivates the game theoretic study of network formation, and our paper
considers one of the most-well studied models, originally proposed by Fabrikant
et al. In it, each of N agents corresponds to a vertex, which can create edges
to other vertices at a cost of alpha each, for some parameter alpha. Every edge
can be freely used by every vertex, regardless of who paid the creation cost.
To reflect the desire to be close to other vertices, each agent's cost function
is further augmented by the sum total of all (graph theoretic) distances to all
other vertices.
  Previous research proved that for many regimes of the (alpha, N) parameter
space, the total social cost (sum of all agents' costs) of every Nash
equilibrium is bounded by at most a constant multiple of the optimal social
cost. In algorithmic game theoretic nomenclature, this approximation ratio is
called the price of anarchy. In our paper, we significantly sharpen some of
those results, proving that for all constant non-integral alpha > 2, the price
of anarchy is in fact 1+o(1), i.e., not only is it bounded by a constant, but
it tends to 1 as N tends to infinity. For constant integral alpha >= 2, we show
that the price of anarchy is bounded away from 1. We provide quantitative
estimates on the rates of convergence for both results.


title: Nested composite NOT gates for quantum computation

abstract:
  Composite pulses provide a simple means for constructing quantum logic gates
which are robust to small errors in the control fields used to implement them.
Here I describe how antisymmetric composite NOT gates can be nested to produce
gates with arbitrary tolerance of errors.


title: Perturbative 3-charge microstate geometries in six dimensions

abstract:
  We construct a set of supersymmetric geometries that represent regular
microstates of the D1-D5-P 3-charge system, using the solution generating
technique of hep-th/0311092. These solutions are constructed as perturbations
around the maximally rotating D1-D5 solution at the linear order, and depend on
the coordinate of S^1 on which the D1- and D5-branes are wrapped. In the
framework of six-dimensional supergravity developed by Gutowski, Martelli and
Reall [hep-th/0306235], these solutions have a 4-dimensional base that depend
on the S^1 coordinate v. The v-dependent base is expected of the superstratum
solutions which are parametrized by arbitrary surfaces, and these solutions
give a modest step toward their explicit construction.


title: The first colliders: AdA, VEP-1 and Princeton-Stanford

abstract: We discuss the first three particle colliders : AdA, VEP-1 and CBX


title:
Unconventional Fulde-Ferrell-Larkin-Ovchinnikov pairing states in a
  Fermi gas with spin-orbit coupling

abstract:
  We study the phase diagram in a two-dimensional Fermi gas with the synthetic
spin-orbit coupling that has recently been realized experimentally. In
particular, we characterize in detail the properties and the stability region
of the unconventional Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) states in such a
system, which are induced by spin-orbit coupling and Fermi surface asymmetry.
We identify several distinct nodal FFLO states by studying the topology of
their respective gapless contours in momentum space. We then examine the phase
structure and the number density distributions in a typical harmonic trapping
potential under the local density approximation. Our studies provide detailed
information on the FFLO pairing states with spin-orbit coupling and Fermi
surface asymmetry, and will facilitate experimental detection of these
interesting pairing states in the future.


title: Instantons and Extreme Value Statistics of Random Matrices

abstract:
  We discuss the distribution of the largest eigenvalue of a random N x N
Hermitian matrix. Utilising results from the quantum gravity and string theory
literature it is seen that the orthogonal polynomials approach, first
introduced by Majumdar and Nadal, can be extended to calculate both the left
and right tail large deviations of the maximum eigenvalue. This framework does
not only provide computational advantages when considering the left and right
tail large deviations for general potentials, as is done explicitly for the
first multi-critical potential, but it also offers an interesting
interpretation of the results. In particular, it is seen that the left tail
large deviations follow from a standard perturbative large N expansion of the
free energy, while the right tail large deviations are related to the
non-perturbative expansion and thus to instanton corrections. Considering the
standard interpretation of instantons as tunnelling of eigenvalues, we see that
the right tail rate function can be identified with the instanton action which
in turn can be given as a simple expression in terms of the spectral curve.
From the string theory point of view these non-perturbative corrections
correspond to branes and can be identified with FZZT branes.

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


title: From homotopy to Ito calculus and Hodge theory

abstract:
  We begin with a deformation of a differential graded algebra by adding time
and using a homotopy. It is shown that the standard formulae of It\^o calculus
are an example, with four caveats: First, it says nothing about probability.
Second, it assumes smooth functions. Third, it deforms all orders of forms, not
just first order. Fourth, it also deforms the product of the DGA. An
isomorphism between the deformed and original DGAs may be interpreted as the
transformation rule between the Stratonovich and classical calculus (again no
probability). The isomorphism can be used to construct covariant derivatives
with the deformed calculus. We apply the deformation in noncommutative
geometry, to the Podle\'s sphere $S^2_q$. This involves the Hodge theory of
$S^2_q$.