title: Silent error detection in numerical time-stepping schemes

abstract:
  Errors due to hardware or low level software problems, if detected, can be
fixed by various schemes, such as recomputation from a checkpoint. Silent
errors are errors in application state that have escaped low-level error
detection. At extreme scale, where machines can perform astronomically many
operations per second, silent errors threaten the validity of computed results.
  We propose a new paradigm for detecting silent errors at the application
level. Our central idea is to frequently compare computed values to those
provided by a cheap checking computation, and to build error detectors based on
the difference between the two output sequences. Numerical analysis provides us
with usable checking computations for the solution of initial-value problems in
ODEs and PDEs, arguably the most common problems in computational science.
Here, we provide, optimize, and test methods based on Runge-Kutta and linear
multistep methods for ODEs, and on implicit and explicit finite difference
schemes for PDEs. We take the heat equation and Navier-Stokes equations as
examples. In tests with artificially injected errors, this approach effectively
detects almost all meaningful errors, without significant slowdown.


title:
Genome-wide scan of 29,141 African Americans finds no evidence of
  selection since admixture

abstract:
  We scanned through the genomes of 29,141 African Americans, searching for
loci where the average proportion of African ancestry deviates significantly
from the genome-wide average. We failed to find any genome-wide significant
deviations, and conclude that any selection in African Americans since
admixture is sufficiently weak that it falls below the threshold of our power
to detect it using a large sample size. These results stand in contrast to the
findings of a recent study of selection in African Americans. That study, which
had 15 times fewer samples, reported six loci with significant deviations. We
show that the discrepancy is likely due to insufficient correction for multiple
hypothesis testing in the previous study. The same study reported 14 loci that
showed greater population differentiation between African Americans and
Nigerian Yoruba than would be expected in the absence of natural selection.
Four such loci were previously shown to be genome-wide significant and likely
to be affected by selection, but we show that most of the 10 additional loci
are likely to be false positives. Additionally, the most parsimonious
explanation for the loci that have significant evidence of unusual
differentiation in frequency between Nigerians and Africans Americans is
selection in Africa prior to their forced migration to the Americas.


title:
Dispersion in Neptune's Zonal Wind Velocities from NIR Keck AO
  Observations in July 2009

abstract:
  We report observations of Neptune made in H-(1.4-1.8 {\mu}m) and K'-(2.0-2.4
{\mu}m) bands on 14 and 16 July 2009 from the 10-m W.M. Keck II Telescope using
the near-infrared camera NIRC2 coupled to the Adaptive Optics (AO) system. We
track the positions of 54 bright atmospheric features over a few hours to
derive their zonal and latitudinal velocities, and perform radiative transfer
modeling to measure the cloud-top pressures of 50 features seen simultaneously
in both bands.
  We observe one South Polar Feature (SPF) on 14 July and three SPFs on 16 July
at ~65 deg S. The SPFs observed on both nights are different features,
consistent with the high variability of Neptune's storms.
  There is significant dispersion in Neptune's zonal wind velocities about the
smooth Voyager wind profile fit of Sromovsky et al., Icarus 105, 140 (1993),
much greater than the upper limit we expect from vertical wind shear, with the
largest dispersion seen at equatorial and southern mid-latitudes. Comparison of
feature pressures vs. residuals in zonal velocity from the smooth Voyager wind
profile also directly reveals the dominance of mechanisms over vertical wind
shear in causing dispersion in the zonal winds.
  Vertical wind shear is not the primary cause of the difference in dispersion
and deviation in zonal velocities between features tracked in H-band on 14 July
and those tracked in K'-band on 16 July. Dispersion in the zonal velocities of
features tracked over these short time periods is dominated by one or more
mechanisms, other than vertical wind shear, that can cause changes in the
dispersion and deviation in the zonal velocities on timescales of hours to
days.


title:
Topology of the planar phase of superfluid $^3$He and bulk-boundary
  correspondence for three dimensional topological superconductors

abstract:
  We provide topological classification of possible phases with the symmetry of
the planar phase of superfluid $^3$He. Compared to the B-phase (class DIII in
classification of Altland and Zirnbauer), it has an additional symmetry, which
modifies the topology. We analyze the topology in terms of explicit mappings
from the momentum space and also discuss explicitly topological invariants for
the B-phase. We further show, how the bulk-boundary correspondence for the 3D
B-phase can be inferred from that for the 2D planar phase. A general condition
is derived for the existence of topologically stable zero modes at the surfaces
of 3D superconductors with class DIII symmetries.


title:
Analysis & Prediction of Sales Data in SAP-ERP System using Clustering
  Algorithms

abstract:
  Clustering is an important data mining technique where we will be interested
in maximizing intracluster distance and also minimizing intercluster distance.
We have utilized clustering techniques for detecting deviation in product sales
and also to identify and compare sales over a particular period of time.
Clustering is suited to group items that seem to fall naturally together, when
there is no specified class for any new item. We have utilizedannual sales data
of a steel major to analyze Sales Volume & Value with respect to dependent
attributes like products, customers and quantities sold. The demand for steel
products is cyclical and depends on many factors like customer profile,
price,Discounts and tax issues. In this paper, we have analyzed sales data with
clustering algorithms like K-Means&EMwhichrevealed many interesting
patternsuseful for improving sales revenue and achieving higher sales volume.
Our study confirms that partition methods like K-Means & EM algorithms are
better suited to analyze our sales data in comparison to Density based methods
like DBSCAN & OPTICS or Hierarchical methods like COBWEB.


title: Magnetic field decay of magnetars in supernova remnants

abstract:
  In this paper, we modify our previous research carefully, and derive a new
expression of electron energy density in superhigh magnetic fields. Based on
our improved model, we re-compute the electron capture rates and the magnetic
fields' evolutionary timescales $t$ of magnetars. According to the calculated
results, the superhigh magnetic fields may evolve on timescales $\sim
(10^{6}-10^{7})$ yrs for common magnetars, and the maximum timescale of the
field decay, $t\approx 2.9507 \times 10^{6}$ yrs, corresponding to an initial
internal magnetic field $B_{\rm 0}= 3.0 \times 10^ {15}$ G and an initial inner
temperature $T_{\rm 0}= 2.6 \times 10^ {8}$ K. Motivated by the results of the
neutron star-supernova remnant(SNR) association of Zhang $\&$ Xie(2011), we
calculate the maximum $B_{\rm 0}$ of magnetar progenitors, $B_{\rm max}\sim
(2.0\times 10^{14}-2.93 \times 10^{15})$ G when $T_{\rm 0}= 2.6 \times 10^ {8}$
K. When $T_{\rm 0}\sim 2.75 \times 10^ {8}-~1.75 \times 10^ {8}$ K, the maximum
$B_{\rm 0}$ will also be in the range of $\sim 10^{14}-10^{15}$ G, not
exceeding the upper limit of magnetic field of a magnetar under our magnetar
model. We also investigate the relationship between the spin-down ages of
magnetars and the ages of their SNRs, and explain why all AXPs associated with
SNRs look older than their real ages, whereas all SGRs associated with SNRs
appear younger than they are.


title:
Transformation of subradiant state to superradiant state in a thick
  resonant medium

abstract:
  The propagation of a step pulse through a thick resonant absorber with
homogeneously broadened absorption line is considered. It is shown that a
specific subradiant state is naturally developed in the absorber due to the
formation of the spatial domains of the atomic coherence with opposite phases.
It is proposed to divide the absorber into slices in accord with these domains
and place the phase shifters in front of the first slice and between the other
slices. If the phase shifters are switched on simultaneously at a particular
moment of time, elapsed from the beginning of the step pulse, a strong sharp
pulse is generated at the output of the last slice of the absorber. The effect
is explained by the phasing of the atomic coherence along all slices of the
absorber, which transforms subradiant state of atom-field system to
superradiant state.


title:
Degrees of Freedom of MIMO Cellular Networks: Decomposition and Linear
  Beamforming Design

abstract:
  This paper investigates the symmetric degrees of freedom (DoF) of MIMO
cellular networks with G cells and K users per cell, having N antennas at each
base station and M antennas at each user. In particular, we investigate
achievability techniques based on either decomposition with asymptotic
interference alignment (IA) or linear beamforming schemes, and show that there
are distinct regimes of (G,K,M,N) where one outperforms the other. We first
note that both one-sided and two-sided decomposition with asymptotic IA achieve
the same degrees of freedom. We then establish specific antenna configurations
under which the DoF achieved using decomposition based schemes is optimal by
deriving a set of outer bounds on the symmetric DoF. For linear beamforming
schemes, we first focus on small networks and propose a structured approach to
linear beamforming based on a notion called packing ratios. Packing ratio
describes the interference footprint or shadow cast by a set of transmit
beamformers and enables us to identify the underlying structures for aligning
interference. Such a structured beamforming design can be shown to achieve the
optimal spatially normalized DoF (sDoF) of two-cell two-user/cell network and
the two-cell three-user/cell network. For larger networks, we develop an
unstructured approach to linear interference alignment, where transmit
beamformers are designed to satisfy conditions for IA without explicitly
identifying the underlying structures for IA. The main numerical insight of
this paper is that such an approach appears to be capable of achieving the
optimal sDoF for MIMO cellular networks in regimes where linear beamforming
dominates asymptotic decomposition, and a significant portion of sDoF
elsewhere. Remarkably, polynomial identity test appears to play a key role in
identifying the boundary of the achievable sDoF region in the former case.


title: Chimera states: The Existence Criteria Revisited

abstract:
  Chimera states, representing a spontaneous break-up of a population of
identical oscillators that are identically coupled, into sub-populations
displaying synchronized and desynchronized behavior, have traditionally been
found to exist in weakly coupled systems and with some form of nonlocal
coupling between the oscillators. Here we show that neither the weak-coupling
approximation nor nonlocal coupling are essential conditions for their
existence. We obtain for the first time amplitude-mediated chimera states in a
system of globally coupled complex Ginzburg-Landau oscillators. We delineate
the dynamical origins for the formation of such states from a bifurcation
analysis of a reduced model equation and also discuss the practical
implications of our discovery of this broader class of chimera states.


title: A one femtojoule athermal silicon modulator

abstract:
  Silicon photonics has emerged as the leading candidate for implementing
ultralow power wavelength division multiplexed communication networks in
high-performance computers, yet current components (lasers, modulators,
filters, and detectors) consume too much power for the femtojouleclass links
that will ultimately be required. Here, we propose, demonstrate, and
characterize the first modulator to achieve simultaneous high-speed (25-Gb/s),
low voltage (0.5VPP) and efficient 1-fJ/bit error-free operation while
maintaining athermal operation. Both the low energy and athermal operation were
enabled by a record free-carrier accumulation/depletion response obtained in a
vertical p-n junction device that at 250-pm/V (30-GHz/V) is up to ten times
larger than prior demonstrations. Over a 7.5{\deg}C temperature range, the
massive electro-optic response was used to compensate for thermal drift without
increasing energy consumption and over a 10{\deg}C temperature range,
increasing energy consumption by only 2-fJ/bit. The results represent a new
paradigm in modulator development, one where thermal compensation is achieved
electro-optically.


title: N=2 supersymmetric dynamics for pedestrians

abstract:
  We give a pedagogical introduction to the dynamics of N=2 supersymmetric
systems in four dimensions. The topic ranges from the Lagrangian and the
Seiberg-Witten solutions of SU(2) gauge theories to Argyres-Douglas CFTs and
Gaiotto dualities.
  This is a write-up of the author's lectures at Tohoku University, Nagoya
University and Rikkyo University. Comments will be appreciated.


title: Finding galaxies with unusual HI content

abstract:
  Observations show that galaxies in galaxy clusters are strongly influenced by
their environment. There is growing evidence that some galaxies in groups show
similar properties to galaxies in clusters, such as redder colours and gas
deficiency, highlighting that environmental processes are also effective on
galaxy group scales. The question is though, which mechanisms are important in
low density environments? To answer this, we identify gas deficient galaxies to
investigate recent or ongoing environmental processes, such as gas stripping.
We are using scaling relations between the neutral hydrogen (HI) content and
optical properties of galaxies to identify galaxies with significantly less HI
than an average galaxy of the same type. We derive new, multi wavelength
HI-optical scaling relations using the HI Parkes All Sky Survey (HIPASS) with
optical and near infrared datasets. We also show our preliminary results from
observations of a sample of 6 HI-deficient galaxies, which we identified in low
density environments.


title:
A Bayesian linear model for the high-dimensional inverse problem of
  seismic tomography

abstract:
  We apply a linear Bayesian model to seismic tomography, a high-dimensional
inverse problem in geophysics. The objective is to estimate the
three-dimensional structure of the earth's interior from data measured at its
surface. Since this typically involves estimating thousands of unknowns or
more, it has always been treated as a linear(ized) optimization problem. Here
we present a Bayesian hierarchical model to estimate the joint distribution of
earth structural and earthquake source parameters. An ellipsoidal spatial prior
allows to accommodate the layered nature of the earth's mantle. With our
efficient algorithm we can sample the posterior distributions for large-scale
linear inverse problems and provide precise uncertainty quantification in terms
of parameter distributions and credible intervals given the data. We apply the
method to a full-fledged tomography problem, an inversion for upper-mantle
structure under western North America that involves more than 11,000
parameters. In studies on simulated and real data, we show that our approach
retrieves the major structures of the earth's interior as well as classical
least-squares minimization, while additionally providing uncertainty
assessments.


title: Stochastic approximation of score functions for Gaussian processes

abstract:
  We discuss the statistical properties of a recently introduced unbiased
stochastic approximation to the score equations for maximum likelihood
calculation for Gaussian processes. Under certain conditions, including bounded
condition number of the covariance matrix, the approach achieves $O(n)$ storage
and nearly $O(n)$ computational effort per optimization step, where $n$ is the
number of data sites. Here, we prove that if the condition number of the
covariance matrix is bounded, then the approximate score equations are nearly
optimal in a well-defined sense. Therefore, not only is the approximation
efficient to compute, but it also has comparable statistical properties to the
exact maximum likelihood estimates. We discuss a modification of the stochastic
approximation in which design elements of the stochastic terms mimic patterns
from a $2^n$ factorial design. We prove these designs are always at least as
good as the unstructured design, and we demonstrate through simulation that
they can produce a substantial improvement over random designs. Our findings
are validated by numerical experiments on simulated data sets of up to 1
million observations. We apply the approach to fit a space-time model to over
80,000 observations of total column ozone contained in the latitude band
$40^{\circ}$-$50^{\circ}$N during April 2012.


title:
Spatial Throughput Characterization in Cognitive Radio Networks with
  Threshold-Based Opportunistic Spectrum Access

abstract:
  This paper studies the opportunistic spectrum access (OSA) of the secondary
users in a large-scale overlay cognitive radio (CR) network. Two
threshold-based OSA schemes, namely the primary receiver assisted (PRA)
protocol and the primary transmitter assisted (PTA) protocol, are investigated.
Under the PRA/PTA protocol, a secondary transmitter (ST) is allowed to access
the spectrum only when the maximum signal power of the received beacons/pilots
sent from the active primary receivers/transmitters (PRs/PTs) is lower than a
certain threshold. To measure the resulting transmission opportunity for the
secondary users by the proposed OSA protocols, the concept of spatial
opportunity, which is defined as the probability that an arbitrary location in
the primary network is detected as a spatial spectrum hole, is introduced and
then evaluated by applying tools from stochastic geometry. Based on spatial
opportunity, the coverage (non-outage transmission) performance in the overlay
CR network is analyzed. With the obtained results of spatial opportunity and
coverage probability, we finally characterize the spatial throughput, which is
defined as the average spatial density of successful transmissions in the
primary/secondary network, under the PRA and PTA protocols, respectively.


title: Plurisubharmonicity of Bergman Kernels on generalized annuli

abstract:
  Let $A_\zeta=\Omega-\overline{\rho(\zeta)\cdot\Omega}$ be a family of
generalized annuli over a domain $U$. We show that the logarithm $\log
K_{\zeta}(z)$ of the Bergman kernel $K_{\zeta}(z)$ of $A_\zeta$ is
plurisubharmonic provided $\rho\in PSH(U)$. It is remarkable that $A_\zeta$ is
non-pseudoconvex when the dimension of $A_\zeta$ is larger than one. For
standard annuli in ${\mathbb C}$, we obtain an interesting formula for
$\partial^2 \log K_{\zeta}/\partial \zeta\partial\bar{\zeta}$, as well as its
boundary behavior.


title:
Penalty Methods with Stochastic Approximation for Stochastic Nonlinear
  Programming

abstract:
  In this paper, we propose a class of penalty methods with stochastic
approximation for solving stochastic nonlinear programming problems. We assume
that only noisy gradients or function values of the objective function are
available via calls to a stochastic first-order or zeroth-order oracle. In each
iteration of the proposed methods, we minimize an exact penalty function which
is nonsmooth and nonconvex with only stochastic first-order or zeroth-order
information available. Stochastic approximation algorithms are presented for
solving this particular subproblem. The worst-case complexity of calls to the
stochastic first-order (or zeroth-order) oracle for the proposed penalty
methods for obtaining an $\epsilon$-stochastic critical point is analyzed.


title:
To the Origin of Anomalous Torque Acting on a Rotating Magnetized Ball
  in Vacuum

abstract:
  The magnitude of the anomalous torque acting on a rotating magnetized ball in
vacuum is specified. Its value is shown to depend on the magnetic field
structure inside the body.


title: Riemann problem for a particle-fluid coupling

abstract:
  We present a model of coupling between a point wise particle and a
compressible inviscid fluid following the Euler equations. The interaction
between the fluid and the particle is achieved through a drag force. It writes
as the product of a discontinuous function and a Dirac measure. After defining
the solution, we solve the Riemann problem with a fixed particle for arbitrary
data. We exhibit a set of condition on the drag force under which there exists
a unique self-similar solution.


title: Fiscal shocks and asymmetric effects: a comparative analysis

abstract:
  We empirically test the effects of unanticipated fiscal policy shocks on the
growth rate and the cyclical component of real private output and reveal
different types of asymmetries in fiscal policy implementation. The data used
are quarterly U.S. observati ons over the period 1967:1 to 2011:4. In doing so,
we use both a vector autoregressive and the novel support vector machines
systems in order to extract the fiscal policy shocks series. The latter has
never been used before in a similar macroeconomic setting. Within our research
framework, in order to test the robustness of our results to alternative
aggregate money supply definitions we use two alternative moentary aggregates.
These are the commonly reported by central banks and policy makers simple sum
monetary aggregates at the MZM level of aggregation and the alternative CFS
Divisia MZM aggregate. From each of these four systems we extracted four types
of shocks: a negative and a positive government spending shock and a negative
and a positive government revenue shock. These eight different types of
unanticipated fiscal policy shocks are next used to empirically examine their
effects on the growth rate and the cyclical component of real private GNP in
two sets of regressions: one that assumes only contemporaneous effects of the
shocks on output and one that is augmented with four lags of each fiscal shock.


title: Matrix Flavor Brane and Dual Wilson Line

abstract:
  We study a novel non-Abelian matrix configuration of probe D-branes in AdS5.
This configuration gives rise to a new D-brane phenomenon related to the known
"Myers effect" in the context of holography. It is dual to a deformation of the
field theory by a Wilson line threaded fermion bilinear. We study the two point
function of these short Wilson lines from both the non-Abelian DBI action and a
classical string world sheet calculation and identify the region where they
agree. We also study a related configuration where the non-Abelian nature of
the embedding functions is enhanced by a background flux as in the Myers
effect.


title: Inhomogeneous cosmology in the cosmic rest frame without dark stuff

abstract:
  We study Einstein's equations with an isotropic but inhomogeneous metric in
the cosmic rest frame. The equations are solved perturbatively in the late
Universe. The leading plus next-to-leading order results agree with
observations without using a cosmological constant or dark matter.


title: Structural Induction Principles for Functional Programmers

abstract:
  User defined recursive types are a fundamental feature of modern functional
programming languages like Haskell, Clean, and the ML family of languages.
Properties of programs defined by recursion on the structure of recursive types
are generally proved by structural induction on the type. It is well known in
the theorem proving community how to generate structural induction principles
from data type declarations. These methods deserve to be better know in the
functional programming community. Existing functional programming textbooks
gloss over this material. And yet, if functional programmers do not know how to
write down the structural induction principle for a new type - how are they
supposed to reason about it? In this paper we describe an algorithm to generate
structural induction principles from data type declarations. We also discuss
how these methods are taught in the functional programming course at the
University of Wyoming. A Haskell implementation of the algorithm is included in
an appendix.


title: Fast and accurate CMB computations in non-flat FLRW universes

abstract:
  We present a new method for calculating CMB anisotropies in a non-flat
Friedmann universe, relying on a very stable algorithm for the calculation of
hyperspherical Bessel functions, that can be pushed to arbitrary precision
levels. We also introduce a new approximation scheme which gradually takes over
in the flat space limit, and significant speeds-up calculations. Our method is
implemented in the Boltzmann code CLASS. It can be used to benchmark the
accuracy of the CAMB code in curved space, which is found to match
expectations. For default precision settings, corresponding to 0.1% for scalar
temperature spectra and 0.2% for scalar polarisation spectra, our code is two
to three times faster, depending on curvature. We also simplify the temperature
and polarisation source terms significantly, so the different contributions to
the $C_\ell$'s are easy to identify inside the code.


title: From Lock Freedom to Progress Using Session Types

abstract:
  Inspired by Kobayashi's type system for lock freedom, we define a behavioral
type system for ensuring progress in a language of binary sessions. The key
idea is to annotate actions in session types with priorities representing the
urgency with which such actions must be performed and to verify that processes
perform such actions with the required priority. Compared to related systems
for session-based languages, the presented type system is relatively simpler
and establishes progress for a wider range of processes.


title: Session Types with Runtime Adaptation: Overview and Examples

abstract:
  In recent work, we have developed a session types discipline for a calculus
that features the usual constructs for session establishment and communication,
but also two novel constructs that enable communicating processes to be
stopped, duplicated, or discarded at runtime. The aim is to understand whether
known techniques for the static analysis of structured communications scale up
to the challenging context of context-aware, adaptable distributed systems, in
which disciplined interaction and runtime adaptation are intertwined concerns.
In this short note, we summarize the main features of our session-typed
framework with runtime adaptation, and recall its basic correctness properties.
We illustrate our framework by means of examples. In particular, we present a
session representation of supervision trees, a mechanism for enforcing
fault-tolerant applications in the Erlang language.


title: Session Types in Abelian Logic

abstract:
  There was a PhD student who says "I found a pair of wooden shoes. I put a
coin in the left and a key in the right. Next morning, I found those objects in
the opposite shoes." We do not claim existence of such shoes, but propose a
similar programming abstraction in the context of typed lambda calculi. The
result, which we call the Amida calculus, extends Abramsky's linear lambda
calculus LF and characterizes Abelian logic.


title: Embedding Session Types in HML

abstract:
  Recent work on the enhancement of multiparty session types with logical
annotations enable the effective verification of properties on (1) the
structure of the conversations, (2) the sorts of the messages, and (3) the
actual values exchanged. In [3] we extend this work to enable the specification
and verification of mutual effects of multiple cross-session interactions. Here
we give a sound and complete embedding into the Hennessy-Milner logic to
justify the expressiveness of the approach in [3] and to provide it with a
logical background that will enable us to compare it with similar approaches.


title: Coinductive Big-Step Semantics for Concurrency

abstract:
  In a paper presented at SOS 2010, we developed a framework for big-step
semantics for interactive input-output in combination with divergence, based on
coinductive and mixed inductive-coinductive notions of resumptions, evaluation
and termination-sensitive weak bisimilarity. In contrast to standard
inductively defined big-step semantics, this framework handles divergence
properly; in particular, runs that produce some observable effects and then
diverge, are not "lost". Here we scale this approach for shared-variable
concurrency on a simple example language. We develop the metatheory of our
semantics in a constructive logic.


title:
The Glasgow Parallel Reduction Machine: Programming Shared-memory
  Many-core Systems using Parallel Task Composition

abstract:
  We present the Glasgow Parallel Reduction Machine (GPRM), a novel, flexible
framework for parallel task-composition based many-core programming. We allow
the programmer to structure programs into task code, written as C++ classes,
and communication code, written in a restricted subset of C++ with functional
semantics and parallel evaluation. In this paper we discuss the GPRM, the
virtual machine framework that enables the parallel task composition approach.
We focus the discussion on GPIR, the functional language used as the
intermediate representation of the bytecode running on the GPRM. Using examples
in this language we show the flexibility and power of our task composition
framework. We demonstrate the potential using an implementation of a merge sort
algorithm on a 64-core Tilera processor, as well as on a conventional Intel
quad-core processor and an AMD 48-core processor system. We also compare our
framework with OpenMP tasks in a parallel pointer chasing algorithm running on
the Tilera processor. Our results show that the GPRM programs outperform the
corresponding OpenMP codes on all test platforms, and can greatly facilitate
writing of parallel programs, in particular non-data parallel algorithms such
as reductions.


title: Session Types Go Dynamic or How to Verify Your Python Conversations

abstract:
  This paper presents the first implementation of session types in a
dynamically-typed language - Python. Communication safety of the whole system
is guaranteed at runtime by monitors that check the execution traces comply
with an associated protocol. Protocols are written in Scribble, a choreography
description language based on multiparty session types, with addition of logic
formulas for more precise behaviour properties. The presented framework
overcomes the limitations of previous works on the session types where all
endpoints should be statically typed so that they do not permit
interoperability with untyped participants. The advantages, expressiveness and
performance of dynamic protocol checking are demonstrated through use case and
benchmarks.


title: Towards deductive verification of MPI programs against session types

abstract:
  The Message Passing Interface (MPI) is the de facto standard message-passing
infrastructure for developing parallel applications. Two decades after the
first version of the library specification, MPI-based applications are nowadays
routinely deployed on super and cluster computers. These applications, written
in C or Fortran, exhibit intricate message passing behaviours, making it hard
to statically verify important properties such as the absence of deadlocks. Our
work builds on session types, a theory for describing protocols that provides
for correct-by-construction guarantees in this regard. We annotate MPI
primitives and C code with session type contracts, written in the language of a
software verifier for C. Annotated code is then checked for correctness with
the software verifier. We present preliminary results and discuss the
challenges that lie ahead for verifying realistic MPI program compliance
against session types.


title: Static Application-Level Race Detection in STM Haskell using Contracts

abstract:
  Writing concurrent programs is a hard task, even when using high-level
synchronization primitives such as transactional memories together with a
functional language with well-controlled side-effects such as Haskell, because
the interferences generated by the processes to each other can occur at
different levels and in a very subtle way. The problem occurs when a thread
leaves or exposes the shared data in an inconsistent state with respect to the
application logic or the real meaning of the data. In this paper, we propose to
associate contracts to transactions and we define a program transformation that
makes it possible to extend static contract checking in the context of STM
Haskell. As a result, we are able to check statically that each transaction of
a STM Haskell program handles the shared data in a such way that a given
consistency property, expressed in the form of a user-defined boolean function,
is preserved. This ensures that bad interference will not occur during the
execution of the concurrent program.


title: Minimising virtual machine support for concurrency

abstract:
  Co-operative and pre-emptive scheduling are usually considered to be
complementary models of threading. In the case of virtual machines, we show
that they can be unified using a single concept, the bounded execution of a
thread of control, essentially providing a first-class representation of a
computation as it is reduced. Furthermore this technique can be used to surface
the thread scheduler of a language into the language itself, allowing programs
to provide their own schedulers without any additional support in the virtual
machine, and allowing the same virtual machine to support different thread
models simultaneously and without re-compilation.


title:
Simulation of radiation transfer and coherent backscattering in nematic
  liquid crystals

abstract:
  We consider the multiple scattering of light by fluctuations of the director
in a nematic liquid crystal. Using methods of numerical simulation the peak of
the coherent backscattering and the coefficients of anisotropic diffusion are
calculated. The calculations were carried out without simplifying assumptions
on the properties of the liquid crystal. The process of multiple scattering was
simulated as a random walk of photons in the medium. We investigated in detail
the transition to the diffusion regime. The dependence of the diffusion
coefficients on the applied magnetic field and the wavelength of light were
studied. The results of simulation showed a non-monotonic dependence of the
diffusion coefficients on the external magnetic field. A qualitative
explanation of this behaviour was suggested using a simple scalar model. For
calculation of the peak of the coherent backscattering we used the
semianalytical approach as long as in nematic liquid crystals this peak is
extremely narrow. The parameters of backscattering peak and of diffusion
coefficients which were found in numerical simulations were compared with the
experimental data and the results of analytical calculation.


title:
Phishing Detection by determining reliability factor using rough set
  theory

abstract:
  Phishing is a common online weapon, used against users, by Phishers for
acquiring a confidential information through deception. Since the inception of
internet, nearly everything, ranging from money transaction to sharing
information, is done online in most parts of the world. This has also given
rise to malicious activities such as Phishing. Detecting Phishing is an
intricate process due to complexity, ambiguity and copious amount of
possibilities of factors responsible for phishing . Rough sets can be a
powerful tool, when working on such kind of Applications containing vague or
imprecise data. This paper proposes an approach towards Phishing Detection
Using Rough Set Theory. The Thirteen basic factors, directly responsible
towards Phishing, are grouped into four Strata. Reliability Factor is
determined on the basis of the outcome of these strata, using Rough Set Theory
. Reliability Factor determines the possibility of a suspected site to be Valid
or Fake. Using Rough set Theory most and the least influential factors towards
Phishing are also determined.


title:
Improving circuit miniaturization and its efficiency using Rough Set
  Theory

abstract:
  High-speed, accuracy, meticulousness and quick response are notion of the
vital necessities for modern digital world. An efficient electronic circuit
unswervingly affects the maneuver of the whole system. Different tools are
required to unravel different types of engineering tribulations. Improving the
efficiency, accuracy and low power consumption in an electronic circuit is
always been a bottle neck problem. So the need of circuit miniaturization is
always there. It saves a lot of time and power that is wasted in switching of
gates, the wiring-crises is reduced, cross-sectional area of chip is reduced,
the number of transistors that can implemented in chip is multiplied many
folds. Therefore to trounce with this problem we have proposed an Artificial
intelligence (AI) based approach that make use of Rough Set Theory for its
implementation. Theory of rough set has been proposed by Z Pawlak in the year
1982. Rough set theory is a new mathematical tool which deals with uncertainty
and vagueness. Decisions can be generated using rough set theory by reducing
the unwanted and superfluous data. We have condensed the number of gates
without upsetting the productivity of the given circuit. This paper proposes an
approach with the help of rough set theory which basically lessens the number
of gates in the circuit, based on decision rules.


title:
Reversible Transient Nucleation in Ionic Solutions as the Precursor of
  Ion Crystallization

abstract:
  Molecular dynamics simulations for aqueous sodium chloride solutions were
carried out at various concentrations. Supplementary to the Debye-H\"uckel
theory, reversible transient nucleation of ions was observed even in dilute
solutions. The average size of formed ion clusters and the lifetime of ion
pairs increase with concentration until the saturation point, when ion clusters
become stable and individual ions adjust their positions to form ordered
lattice structures, leading to irreversible ion crystallization, which is
beyond the description of the classical nucleation theory.


title: Pushing down the Rumin complex to conformally symplectic quotients

abstract:
  Given a contact manifold $M_#$ together with a transversal infinitesimal
automorphism $\xi$, we show that any local leaf space $M$ for the foliation
determined by $\xi$ naturally carries a conformally symplectic (cs-) structure.
Then we show that the Rumin complex on $M_#$ descends to a complex of
differential operators on $M$, whose cohomology can be computed. Applying this
construction locally, one obtains a complex intrinsically associated to any
manifold endowed with a cs-structure, which recovers the generalization of the
so-called Rumin-Seshadri complex to the conformally symplectic setting. The
cohomology of this more general complex can be computed using the push-down
construction.


title: Space-Time Area in Atom Interferometry

abstract:
  It is a commonly stated that the acceleration sensitivity of an atom
interferometer is proportional to the space-time area enclosed between the two
interfering arms. Here we derive the interferometric phase shift for an
extensive class of interferometers, and explore the circumstances in which only
the inertial terms contribute. We then analyse various configurations in light
of this geometric interpretation of the interferometric phase shift.


title: A Separated Cohomologically Complete Module is Complete

abstract:
  We prove two theorems on cohomologically complete complexes. These theorems
are inspired by, and yield an alternative proof of, a recent theorem of P.
Schenzel on complete modules.


title: Hybrid ion, atom and light trap

abstract:
  We present an unique experimental arrangement which permits the simultaneous
trapping and cooling of ions and neutral atoms, within a Fabry-Perot (FP)
cavity. The versatility of this hybrid trap experiment enables a variety of
studies with trapped mixtures. The motivations behind the production of such a
hybrid trap system are explained, followed by details of how the experiment is
put together. Several experiments that have been performed with this system are
presented and some opportunities with this system are discussed. However the
primary emphasis is focussed on the aspects that pertain to the trapped ions,
in this hybrid system.


title: Metal insulator transitions in perovskite SrIrO3 thin films

abstract:
  Understanding of metal insulator transitions in a strongly correlated system,
driven by Anderson localization (disorder) and/or Mott localization
(correlation), is a long standing problem in condensed matter physics. The
prevailing fundamental question would be how these two mechanisms contrive to
accomplish emergent anomalous behaviors. Here, we have grown high quality
perovskite SrIrO3 thin films, containing a strong spin orbit coupled 5d element
Ir, on various substrates such as GdScO3 (110), DyScO3 (110), SrTiO3 (001), and
NdGaO3 (110) with increasing lattice mismatch, in order to carry out a
systematic study on the transport properties. We found that metal insulator
transitions can be induced in this system; by either reducing thickness (on
best lattice matched substrate) or changing degree of lattice strain (by
lattice mismatch between film and substrates) of films. Surprisingly these two
pathways seek two distinct types of metal insulator transitions; the former
falls into disorder driven Anderson type whereas the latter turns out to be of
unconventional Mott-Anderson type with the interplay of disorder and
correlation. More interestingly, in the metallic phases of SrIrO3, unusual
non-Fermi liquid characteristics emerge in resistivity as the resistivity
exponent evolves from from 4/5 to 1 to 3/2 with increasing lattice strain. We
discuss theoretical implications of these phenomena to shed light on the metal
insulator transitions.


title:
Spin Pumping and Inverse Spin Hall Effect in Platinum: The Essential
  Role of Spin-Memory Loss at Metallic Interfaces

abstract:
  Through combined ferromagnetic resonance, spin-pumping and inverse spin Hall
effect experiments in Co|Pt bilayers and Co|Cu|Pt trilayers, we demonstrate
consistent values of spin diffusion length $\ell_{\rm sf}^{\rm Pt}=3.4\pm0.4$
nm and of spin Hall angle $\theta_{\rm SHE}^{\rm Pt}=0.051\pm0.004$ for Pt. Our
data and model emphasize on the partial depolarization of the spin current at
each interface due to spin-memory loss. Our model reconciles the previously
published spin Hall angle values and explains the different scaling lengths for
the ferromagnetic damping and the spin Hall effect induced voltage.


title: Selected Results from STAR Beam Energy Scan Program

abstract:
  Results from the Beam Energy Scan (BES) program conducted by STAR experiment
at RHIC are presented. The data from Phase-I of the BES program collected in
Au+Au collisions at center-of-mass energies ($\sqrt{s_{NN}}$) of 7.7, 11.5,
19.6, 27, and 39 GeV cover a wide range of baryon chemical potential $\mu_{B}$
(100--400 MeV) in the QCD phase diagram. Several STAR results from the BES
Phase-I related to "turn-off" of strongly interacting quark--gluon plasma
(sQGP) signatures and signals of QCD phase boundary are reported. In addition
to this, an outlook is presented for the future BES Phase-II program and a
possible fixed target program at STAR.


title:
Linear response of a one-dimensional conductor coupled to a dynamical
  impurity with a Fermi edge singularity

abstract:
  I study the dynamical correlations that a quantum impurity induces in the
Fermi sea to which it is coupled. I consider a quantum transport set-up in
which the impurity can be realised in a double quantum dot. The same
Hamiltonian describes tunnelling states in metallic glasses, and can be mapped
onto the Ohmic spin-boson model. It exhibits a Fermi edge singularity, i.e.
many fermion correlations result in an impurity decay rate with a non-trivial
power law energy dependence. I show that there is a simple relation between
temporal impurity correlations on the one hand, and the linear response of the
Fermi sea to external perturbations on the other. This results in a power law
singularity in the space and time dependence of the non-local polarisability of
the Fermi sea, which can be detected in transport experiments.


title:
Landau level-superfluid modified factor and effective X/$\gamma$-ray
  coefficient of a magnetar

abstract:
  As soon as the energy of electrons near the Fermi surface are higher than
$Q$, the threshold energy of inverse $\beta-$ decay, the electron capture
process will dominate. The resulting high-energy neutrons will destroy
anisotropic ${}^3P_2$ neutron superfluid Cooper pairs. By colliding with the
neutrons produced in the process $n+ (n\uparrow n\downarrow)\longrightarrow n+
n+ n$, the kinetic energy of the outgoing neutrons will be transformed into
thermal energy. The transformed thermal energy would transported from the star
interior to the star surface by conduction, then would be transformed into
radiation energy as soft X-rays and gamma-rays. After a highly efficient
modulation within the pulsar magnetosphere, the surface thermal emission
(mainly soft X/$\gamma$-ray emission) has been shaped into a spectrum with the
observed characteristics of magnetars. By introducing two important parameters:
Landau level-superfluid modified factor and effective X/$\gamma$-ray
coefficient, we numerically simulate the process of magnetar cooling and
magnetic field decay, and then compute magnetars' soft X/$\gamma$-ray
luminosities $L_{X}$. Further, we obtain aschematic diagrams of $L_{X}$ as a
function of magnetic field strength $B$. The observations are compared with the
calculations.


title:
Analytical properties of the quark propagator from truncated
  Dyson-Schwinger equation in complex Euclidean space

abstract:
  In view of the mass spectrum of heavy mesons in vacuum the analytical
properties of the solutions of the truncated Dyson-Schwinger equatio for the
quark propagator within the rainbow approximation are analysed in some detail.
In Euclidean space, the quark propagator is not an analytical function
possessing, in general, an infinite number of singularities (poles) which
hamper to solve the Bethe-Salpeter equation. However, for light mesons (with
masses M_{q\bar q} <= 1 GeV) all singularities are located outside the region
within which the Bethe-Salpeter equation is defined. With an increase of the
considered meson masses this region enlarges and already at masses >= 1 GeV,
the poles of propagators of u,d and s quarks fall within the integration domain
of the Bethe-Salpeter equation. Nevertheless, it is established that for meson
masses up to M_{q\bar q}~=3 GeV only the first, mutually complex conjugated,
poles contribute to the solution. We argue that, by knowing the position of the
poles and their residues, a reliable parametrisation of the quark propagators
can be found and used in numerical procedures of solving the Bethe-Salpeter
equation. Our analysis is directly related to the future physics programme at
FAIR with respect to open charm degrees of freedom.


title:
Modelling of the European Union income distribution by extended
  Yakovenko formula

abstract:
  We found a unified formula for description of the household incomes of all
society classes, for instance, for the European Union in years 2005-2010. The
formula is more general than well known that of Yakovenko et al. because, it
satisfactorily describes not only the household incomes of low- and
medium-income society classes but also the household incomes of the high-income
society class. As a striking result, we found that the high-income society
class almost disappeared in year 2009, in opposite to situation in remaining
years, where this class played a significant role.


title:
Kaon Freeze-out Dynamics in $\sqrt s_{NN}$=200 GeV Au+Au Collisions at
  RHIC

abstract:
  Measurements of three-dimensional correlation functions of like-sign low
transverse momentum kaon pairs from Au+Au collisions at top RHIC energy $\sqrt
s_{NN}$=200 GeV are presented. The extracted kaon source function is narrower
than the pion one and does not have the long tail along the pair transverse
momentum direction. This indicates a much smaller role of long-lived resonance
decays and/or of the emission duration on kaon emission. Three-dimensional
Gaussian shape of the kaon source function can be adequately reproduced by
Therminator simulations with resonance contributions taken into account.
Comparison to pion data at the same energy reveals that the kaon Gaussian radii
in the outward and sideward directions scale with the transverse mass $m_T$. In
the longitudinal direction, unlike at lower SPS energies, the Gaussian radii do
not seem to follow the exact $m_T$ scaling between kaons and pions.


title: Maximal surfaces in anti-de Sitter 3-manifolds with particles

abstract:
  We prove the existence of a unique maximal surface in each anti-de Sitter
(AdS) convex Globally Hyperbolic Maximal (GHM) manifold with particles (that
is, with conical singularities along time-like lines) for cone angles less than
$\pi$. We interpret this result in terms of Teichm\"uller theory, and prove the
existence of a unique minimal Lagrangian diffeomorphism isotopic to the
identity between two hyperbolic surfaces with cone singularities when the cone
angles are the same for both surfaces and are less than $\pi$.


title: Contact hypersurfaces in Kaehler manifolds

abstract:
  A contact hypersurface in a Kaehler manifold is a real hypersurface for which
the induced almost contact metric structure determines a contact structure. We
carry out a systematic study of contact hypersurfaces in Kaehler manifolds. We
then apply these general results to obtain classifications of contact
hypersurfaces with constant mean curvature in the complex quadric
SO(n+2)/SO(n)SO(2) and its noncompact dual space SO(n,2)/SO(n)SO(2) for n > 2.


title:
Asymptotic mean stationarity and absolute continuity of point process
  distributions

abstract:
  This paper relates - for point processes $\Phi$ on $\mathbb{R}$ - two types
of asymptotic mean stationarity (AMS) properties and several absolute
continuity results for the common probability measures emerging from point
process theory. It is proven that $\Phi$ is AMS under the time-shifts if and
only if it is AMS under the event-shifts. The consequences for the accompanying
two types of ergodic theorem are considered. Furthermore, the AMS properties
are equivalent or closely related to several absolute continuity results. Thus,
the class of AMS point processes is characterized in several ways. Many results
from stationary point process theory are generalized for AMS point processes.
To obtain these results, we first use Campbell's equation to rewrite the
well-known Palm relationship for general nonstationary point processes into
expressions which resemble results from stationary point process theory.


title: Quasi-symmetric functions as polynomial functions on Young diagrams

abstract:
  We determine the most general form of a smooth function on Young diagrams,
that is, a polynomial in the interlacing or multirectangular coordinates whose
value depends only on the shape of the diagram. We prove that the algebra of
such functions is isomorphic to quasi-symmetric functions, and give a
noncommutative analog of this result.


title: Evolution of superhigh magnetic fields of magnetars

abstract:
  In this paper, we consider the effect of Landau levels on the decay of
superhigh magnetic fields of magnetars. Applying ${}^3P_2$ anisotropic neutron
superfluid theory yield a second-order differential equation for a superhigh
magnetic field $B$ and its evolutionary timescale $t$. The superhigh magnetic
fields may evolve on timescales $\sim (10^{6}-10^{7})$ yrs for common
magnetars. According to our model, the activity of a magnetar may originate
from instability caused by the high electron Fermi energy.


title: On the long nulls of PSRs J1738-2330 and J1752+2359

abstract:
  This paper compares and contrasts the emission of two high nulling fraction
pulsars, PSRs J1738-2330 and J1752+2359. In both pulsars the emission bursts
appear in a quasi-periodic fashion with typical separations of several hundred
pulses, and in J1738-2330 there is evidence of two underlying periodicities
with memory persisting for at least 11 bursts. By contrast, in J1752+2359 the
pattern coherence is rapidly lost and the burst/null lengths appear to be
selected randomly from their respective quasi-normal distributions. The typical
emission bursts of J1738-2330 exhibit a steady exponential decay of on-pulse
energy accompanied by a flickering emission characterized by short frequent
nulls towards their end. In the bursts of J1752+2359 the flickering is absent,
the decay more pronounced and the energy released during each bright phase is
approximately constant. Unlike J1738-2330, the average profiles for the first
and the last pulses of J1752+2359 bursts differ slightly from the pulsar's
overall profile, hinting at differences between the two pulsars in their
transitions from null to burst state (and vice-versa). During its long null
phases, J1752+2359 is found to emit random weak inter-burst pulses (IBPs) whose
profile peak is somewhat offset with respect to the overall average profile.
Such pulses have no equivalent in J1738-2330 or in any known pulsar hitherto.
They may pervade the entire emission of this pulsar and have a separate
physical origin to normal pulses. On the basis of our comparison we conclude
that a pulsar's nulling fraction, even when high, remains a poor guide to its
detailed subpulse behaviour, as previously found for pulsars with small nulling
fractions.


title:
Clique-Stable Set separation in perfect graphs with no balanced
  skew-partitions

abstract:
  Inspired by a question of Yannakakis on the Vertex Packing polytope of
perfect graphs, we study the Clique-Stable Set Separation in a non-hereditary
subclass of perfect graphs. A cut (B,W) of G (a bipartition of V(G)) separates
a clique K and a stable set S if $K\subseteq B$ and $S\subseteq W$. A
Clique-Stable Set Separator is a family of cuts such that for every clique K,
and for every stable set S disjoint from K, there exists a cut in the family
that separates K and S. Given a class of graphs, the question is to know
whether every graph of the class admits a Clique-Stable Set Separator
containing only polynomially many cuts. It is open for the class of all graphs,
and also for perfect graphs, which was Yannakakis' original question. Here we
investigate on perfect graphs with no balanced skew-partition; the balanced
skew-partition was introduced in the proof of the Strong Perfect Graph Theorem.
Recently, Chudnovsky, Trotignon, Trunck and Vuskovic proved that forbidding
this unfriendly decomposition permits to recursively decompose Berge graphs
using 2-join and complement 2-join until reaching a basic graph, and they found
an efficient combinatorial algorithm to color those graphs. We apply their
decomposition result to prove that perfect graphs with no balanced
skew-partition admit a quadratic-size Clique-Stable Set Separator, by taking
advantage of the good behavior of 2-join with respect to this property. We then
generalize this result and prove that the Strong Erdos-Hajnal property holds in
this class, which means that every such graph has a linear-size biclique or
complement biclique. This property does not hold for all perfect graphs (Fox
2006), and moreover when the Strong Erdos-Hajnal property holds in a hereditary
class of graphs, then both the Erdos-Hajnal property and the polynomial
Clique-Stable Set Separation hold.


title:
Method of Successive Projections for Nonnegative Inverse Singular Value
  problems with Prescribed Structure

abstract:
  The study of solving inverse singular value problems for nonnegative matrices
has been around for decades. It is clear that an inverse singular problem is
trivial if the desirable matrix is not restricted to a certain structure.
Provided with singular values and diagonal entries, this paper presents a
numerical procedure, based on the successive projection process, to solve
inverse singular value problems for nonnegative matrices subject to given
diagonal entries. Even if we focus on the specific type of inverse singular
value problems with prescribed diagonal entries, this entire procedure can be
carried over with little effort to other types of structure. Numerical examples
are used to demonstrate the capacity and efficiency of our method.


title:
Asymptotic behaviors of means of central values of automorphic
  $L$-functions for GL(2)

abstract:
  Let $\mathbb{A}$ be the adele ring of a totally real algebraic number field
$F$. We push forward an explicit computation of a relative trace formula for
periods of automorphic forms along a split torus in $GL(2)$ from a square free
level case done by Masao Tsuzuki, to an arbitrary level case. By using a
relative trace formula, we study central values of automorphic $L$-functions
for cuspidal automorphic representations of $GL(2, \mathbb{A})$ corresponding
to Maass forms with arbitrary level.


title:
Numerical simulation of the electron capture process in a magnetar
  interior

abstract:
  In a superhigh magnetic field, direct Urca reactions can proceed for an
arbitrary proton concentration. Since only the electrons with high energy $E$
($E > Q$, $Q$ is the threshold energy of inverse $\beta-$decay) at large Landau
levels can be captured, we introduce the Landau level effect coefficient $q$
and the effective electron capture rate $\Gamma_{\rm eff}$. By using
$\Gamma_{\rm eff}$, the values of $L_{\rm X}$ and $L_{\rm \nu}$ are calculated,
where and $L_{\rm \nu}$, $L_{\rm X}$ are the average neutrino luminosity of
Anomalous X-ray Pulsars (AXPs) and the average X-ray luminosity of AXPs,
respectively. The complete process of electron capture inside a magnetar is
simulated numerically.


title: Besov regularity for operator equations on patchwise smooth manifolds

abstract:
  We study regularity properties of solutions to operator equations on
patchwise smooth manifolds $\partial\Omega$ such as, e.g., boundaries of
polyhedral domains $\Omega \subset \mathbb{R}^3$. Using suitable biorthogonal
wavelet bases $\Psi$, we introduce a new class of Besov-type spaces
$B_{\Psi,q}^\alpha(L_p(\partial \Omega))$ of functions
$u\colon\partial\Omega\rightarrow\mathbb{C}$. Special attention is paid on the
rate of convergence for best $n$-term wavelet approximation to functions in
these scales since this determines the performance of adaptive numerical
schemes. We show embeddings of (weighted) Sobolev spaces on $\partial\Omega$
into $B_{\Psi,\tau}^\alpha(L_\tau(\partial \Omega))$, $1/\tau=\alpha/2 + 1/2$,
which lead us to regularity assertions for the equations under consideration.
Finally, we apply our results to a boundary integral equation of the second
kind which arises from the double layer ansatz for Dirichlet problems for
Laplace's equation in $\Omega$.


title:
Universal flow-density relation of single-file bicycle, pedestrian and
  car motion

abstract:
  The relation between flow and density is an essential quantitative
characteristic to describe the efficiency of traffic systems. We have performed
experiments with single-file motion of bicycles and compare the results with
previous studies for car and pedestrian motion in similar setups. In the
space-time diagrams we observe three different states of motion (free flow
state, jammed state and stop-and-go waves) in all these systems. Despite of
their obvious differences they are described by a universal fundamental diagram
after proper rescaling of space and time which takes into account the size and
free velocity of the three kinds of agents. This indicates that the
similarities between the systems go deeper than expected.


title: Approximate Hermitian-Yang-Mills structures on semistable Higgs bundles

abstract:
  We review the notions of (weak) Hermitian-Yang-Mills structure and
approximate Hermitian-Yang-Mills structure for Higgs bundles. Then, we
construct the Donaldson functional for Higgs bundles over compact K\"ahler
manifolds and we present some basic properties of it. In particular, we show
that its gradient flow can be written in terms of the mean curvature of the
Hitchin-Simpson connection. We also study some properties of the evolution
equation associated to that functional. Next, we study the problem of the
existence of approximate Hermitian-Yang-Mills structure and its relation with
the algebro-geometric notion of Mumford-Takemoto semistability and we show that
for a Higgs bundle over a compact Riemann surface, the notion of approximate
Hermitian-Yang- Mills structure is in fact the differential-geometric
counterpart of the notion of semistability. Finally, using Donaldson heat flow,
we show that the semistability of a Higgs bundle over a compact K\"ahler
manifold (of every dimension) implies the existence of an approximate
Hermitian-Yang-Mills structure. As a consequence of this we deduce that many
results about Higgs bundles written in terms of approximate
Hermitian-Yang-Mills structures can be translated in terms of semistability.


title: On the Evolution of BM Orionis

abstract:
  BM Orionis, eclipsing binary system that located in the center of Orion
Nebula Cluster posses several enigmatic problems. Its intrinsic nature and
nebular environment make it harder to measure the physical parameters of the
system, but it is believed as Algol type binary where secondary component is
pre-main sequence star with larger radius. To assure this, several stellar
models ($M_1=5.9$ {M_{\odot}} and $M_2=2.0$ {M_{\odot}}) are created and
simulated using MESA. Models with rigid rotation of $\omega=10^{-5}$ rad/s
exhibit considerable similar properties during pre-main sequence stage, but 2.0
{\msun} at assumed age of $\sim10^6$ is $6.46$ times dimmer than observed
secondary star. There must be an external mechanism to fill this luminosity
gap. Then, simulated post-main sequence binary evolution of BM Ori that
involves mass transfer shows that primary star will reach helium sequence with
the mass of $\sim0.8$ {\msun} before second stage mass transfer.


title: Shortest Unique Substring Query Revisited

abstract:
  We revisit the problem of finding shortest unique substring (SUS) proposed
recently by [6]. We propose an optimal $O(n)$ time and space algorithm that can
find an SUS for every location of a string of size $n$. Our algorithm
significantly improves the $O(n^2)$ time complexity needed by [6]. We also
support finding all the SUSes covering every location, whereas the solution in
[6] can find only one SUS for every location. Further, our solution is simpler
and easier to implement and can also be more space efficient in practice, since
we only use the inverse suffix array and longest common prefix array of the
string, while the algorithm in [6] uses the suffix tree of the string and other
auxiliary data structures. Our theoretical results are validated by an
empirical study that shows our algorithm is much faster and more space-saving
than the one in [6].


title: Physical parameters of young M-type stars and brown dwarfs with VOSA

abstract:
  Although M dwarfs are the most common stars in our stellar neighborhood they
are still among the least understood. This class of objects is dominated by
dramatic changes: in their interiors (fully convective, with implications in
angular momentum evolution), in their atmospheres (crossing temperatures where
dust settling occurs), and in their nature (including both, stellar and
substellar objects).
  Populating efficiently our solar neighborhood, they are very well represented
in the databases coming from new and more sensitive surveys that provide
photometry at many wavelength ranges and cover large areas of the sky (few
examples among many others are GALEX, SDSS, 2MASS, WISE and VISTA).
  In this context of opulence of objects and data, the Virtual Observatory
comes in naturally as an excellent framework to efficiently advance in the
knowledge of M-type sources. We put special emphasis in the benefits of using
the new capabilities of VOSA (Virtual Observatory SED Analyzer, Bayo et al.
2008; in operation since 2008 and in constant development) to study large
samples of candidate and confirmed M members of Chamaeleon I.


title:
Integrable dispersionless PDEs arising as commutation condition of pairs
  of vector fields

abstract:
  We review some results about the theory of integrable dispersionless PDEs
arising as commutation condition of pairs of one-parameter families of vector
fields, developed by the authors during the last years. We review, in
particular, the formal aspects of a novel Inverse Spectral Transform including,
as inverse problem, a nonlinear Riemann - Hilbert (NRH) problem, allowing one
i) to solve the Cauchy problem for the target PDE; ii) to construct classes of
RH spectral data for which the NRH problem is exactly solvable; iii) to
construct the longtime behavior of the solutions of such PDE; iv) to establish
if a localized initial datum breaks at finite time. We also comment on the
existence of recursion operators and Backl\"und - Darboux transformations for
integrable dispersionless PDEs.


title: Importance of $1n$-stripping process in the $^{6}$Li+$^{159}$Tb reaction

abstract:
  The inclusive cross sections of the $\alpha$-particles produced in the
reaction $^{6}$Li+$^{159}$Tb have been measured at energies around the Coulomb
barrier. The measured cross sections are found to be orders of magnitude larger
than the calculated cross sections of $^{6}$Li breaking into $\alpha$ and $d$
fragments, thus indicating contributions from other processes. The experimental
cross sections of $1n$-stripping and $1n$-pickup processes have been determined
from an entirely different measurement, reported earlier. Apart from incomplete
fusion and/ $d$-transfer processes, the $1n$-stripping process is found to be a
significant contributor to the inclusive $\alpha$-particle cross sections in
this reaction.


title: Suryakala-Nusantara: Documenting Indonesian Sundials

abstract:
  Sundial is the ancient or classic timekeeper device, especially prior to the
invention of mechanical clock. In the classical Islamic civilization, the daily
movement of the Sun becomes main indicator of praying time, which can be
deduced using sundial. This kind of device probably permeated to Indonesia
during the Islamic acculturation. Since then, the development of astronomical
knowledge, technology, art and architectural in classical Indonesia are
partially reflected into sundial. These historical attractions of sundial
demand comprehensive documentation and investigation of Indonesian sundial
which are rarely found in the current literatures. The required spatial and
temporal information regarding Indonesian sundial can be collected by general
public through citizen science scheme. This concept may answer scientific
curiosity of a research and also educate the people, expose them with science.
In this article, general scheme of citizen science are discussed, its
application for sundial study in Indonesia is proposed as Suryakala-Nusantara
program.


title: The theoretical instability strip of M dwarf stars

abstract:
  The overstability of the fundamental radial mode in M dwarf models was
theoretically predicted by Rodr\'iguez-L\'opez et al. (2012). The periods were
found to be in the ranges ~25-40 min and ~4-8 h, depending on stellar age and
excitation mechanism. We have extended our initial M dwarf model grid in mass,
metallicity, and mixing length parameter. We have also considered models with
boundary conditions from PHOENIX NextGen atmospheres to test their influence on
the pulsation spectra. We find instability of non-radial modes with radial
orders up to k=3, degree l=0-3, including p and g modes, with the period range
extending from 20 min up to 11 h. Furthermore, we find theoretical evidence of
the potential of M dwarfs as solar-like oscillators.


title: Calibration of photomultipliers gain used in the J-PET detector

abstract:
  Photomultipliers are commonly used in commercial PET scanner as devices which
convert light produced in scintillator by gamma quanta from positron-electron
annihilation into electrical signal. For proper analysis of obtained electrical
signal, a photomultiplier gain curve must be known, since gain can be
significantly different even between photomultipliers of the same model. In
this article we describe single photoelectron method used for photomultipliers
calibration applied for J-PET scanner, a novel PET detector being developed at
the Jagiellonian University. Description of calibration method, an example of
calibration curve and gain of few R4998 Hamamatsu photomultipliers are
presented.


title:
Recent results on N* spectroscopy with ANL-Osaka dynamical
  coupled-channels approach

abstract:
  We report our recent effort on the extraction of N*- and Delta*-resonance
parameters (pole masses, coupling constants, etc.) through the comprehensive
analysis of pion- and photon-induced pi N, eta N, K Lambda, and K Sigma
production reactions. The analysis was performed with the ANL-Osaka dynamical
coupled-channels approach, which satisfies the multichannel unitarity of the
S-matrix in the channel space spanned by pi N, eta N, K Lambda, K Sigma, and
also three-body pi pi N that contains rho N, pi Delta, and sigma N resonant
components. Ongoing projects and future plans are also discussed.


title:
Structure-reversibility of a two dimensional reflecting random walk and
  its application to queueing network

abstract:
  We consider a two dimensional reflecting random walk on the nonnegative
integer quadrant. It is assumed that this reflecting random walk has skip free
transitions. We are concerned with its time reversed process assuming that the
stationary distribution exists. In general, the time reversed process may not
be a reflecting random walk. In this paper, we derive necessary and sufficient
conditions for the time reversed process also to be a reflecting random walk.
These conditions are different from but closely related to the product form of
the stationary distribution.


title: Chameleon Fragmentation

abstract:
  A scalar field dark energy candidate could couple to ordinary matter and
photons, enabling its detection in laboratory experiments. Here we study the
quantum properties of the chameleon field, one such dark energy candidate, in
an "afterglow" experiment designed to produce, trap, and detect chameleon
particles. In particular, we investigate the possible fragmentation of a beam
of chameleon particles into multiple particle states due to the highly
non-linear interaction terms in the chameleon Lagrangian. Fragmentation could
weaken the constraints of an afterglow experiment by reducing the energy of the
regenerated photons, but this energy reduction also provides a unique signature
which could be detected by a properly-designed experiment. We show that
constraints from the CHASE experiment are essentially unaffected by
fragmentation for $\phi^4$ and $1/\phi$ potentials, but are weakened for
steeper potentials, and we discuss possible future afterglow experiments.


title:
Voltage-controlled transmission in a dielectric slab doped with the
  quantum dot molecules

abstract:
  Transmission and reflection of an electromagnetic pulse through a dielectric
slab doped with the quantum dot molecules is investigated. It is shown that the
transmitted and reflected pulses depend on the inter-dot tunneling effect and
can be controlled by applying a gate voltage.


title: Thermionic charge transport in CMOS nano-transistors

abstract:
  We report on DC and microwave electrical transport measurements in
silicon-on-insulator CMOS nano-transistors at low and room temperature. At low
source-drain voltage, the DC current and RF response show signs of conductance
quantization. We attribute this to Coulomb blockade resulting from barriers
formed at the spacer-gate interfaces. We show that at high bias transport
occurs thermionically over the highest barrier: Transconductance traces
obtained from microwave scattering-parameter measurements at liquid helium and
room temperature is accurately fitted by a thermionic model. From the fits we
deduce the ratio of gate capacitance and quantum capacitance, as well as the
electron temperature.


title:
Inverse population transfer of the repulsive Bose-Einstein condensate in
  a double-well trap: strong interaction-induced support

abstract:
  An inverse population transfer of the repulsive Bose-Einstein condensate
(BEC) in a weakly bound double-well trap is explored within the 3D
time-dependent Gross-Pitaevskii equation. The model avoids numerous common
approximations (two-mode treatment, time-space factorization, etc) and closely
follows the conditions of Heidelberg experiments, thus providing a realistic
description of BEC dynamics. The transfer is driven by a time-dependent shift
of a barrier separating the left and right wells. It is shown that completeness
and robustness of the process considerably depend on the amplitude and time
profile of the shift velocity. Soft profiles provide the most robust inversion.
The repulsive interaction substantially supports the transfer making it
possible i) in a wide velocity interval and ii) three orders of magnitude
faster than in the ideal BEC.


title:
Universal $\kappa$-Poincar\'e covariant differential calculus over
  $\kappa$-Minkowski space

abstract:
  Unified graded differential algebra, generated by $\kappa$-Minkowski
noncommutative (NC) coordinates, Lorentz generators and anticommuting
one-forms, is constructed. It is compatible with $\kappa$-Poincar\'e-Hopf
algebra. For time- and space-like deformations, the super-Jacobi identities are
not satisfied. By introducing additional generator, interpreted as exterior
derivative, we find a new unique algebra that satisfies all super-Jacobi
identities. It is universal and valid for all type of deformations (time-,
space-, and light-like). For time-like deformations this algebra coincides with
the one in \cite{sitarz}. Different realizations of our algebra in terms of
super-Heisenberg algebra are presented. For light-like deformations we get 4D
bicovariant calculus, with $\kappa$-Poincar\'e-Hopf algebra and present the
corresponding twist, which is written in a new covariant way, using Poincar\'e
generators only. In the time- and space-like case this twist leads to
$\kappa$-Snyder space. Our results might lead to applications in NC quantum
field theories (especially electrodynamics and gauge theories), quantum gravity
models, and Planck scale physics.


title:
Circulant Tensors with Applications to Spectral Hypergraph Theory and
  Stochastic Process

abstract:
  Circulant tensors naturally arise from stochastic process and spectral
hypergraph theory. The joint moments of stochastic processes are symmetric
circulant tensors. The adjacency, Laplacian and signless Laplacian tensors of
circulant hypergraphs are also symmetric circulant tensors. The adjacency,
Laplacian and signless Laplacian tensors of directed circulant hypergraphs are
circulant tensors, but they are not symmetric in general. In this paper, we
study spectral properties of circulant tensors and their applications in
spectral hypergraph theory and stochastic process. We show that in certain
cases, the largest H-eigenvalue of a circulant tensor can be explicitly
identified. In particular, the largest H-eigenvalue of a nonnegative circulant
tensor can be explicitly identified. This confirms the results in circulant
hypergraphs and directed circulant hypergraphs. We prove that an even order
circulant B$_0$ tensor is always positive semi-definite. This shows that the
Laplacian tensor and the signless Laplacian tensor of a directed circulant
even-uniform hypergraph are positive semi-definite. If a stochastic process is
$m$th order stationary, where $m$ is even, then its $m$th order moment, which
is a circulant tensor, must be positive semi-definite. In this paper, we give
various conditions for a circulant tensor to be positive semi-definite.


title:
The GWmodel R package: Further Topics for Exploring Spatial
  Heterogeneity using Geographically Weighted Models

abstract:
  In this study, we present a collection of local models, termed geographically
weighted (GW) models, that can be found within the GWmodel R package. A GW
model suits situations when spatial data are poorly described by the global
form, and for some regions the localised fit provides a better description. The
approach uses a moving window weighting technique, where a collection of local
models are estimated at target locations. Commonly, model parameters or outputs
are mapped so that the nature of spatial heterogeneity can be explored and
assessed. In particular, we present case studies using: (i) GW summary
statistics and a GW principal components analysis; (ii) advanced GW regression
fits and diagnostics; (iii) associated Monte Carlo significance tests for
non-stationarity; (iv) a GW discriminant analysis; and (v) enhanced kernel
bandwidth selection procedures. General Election data sets from the Republic of
Ireland and US are used for demonstration. This study is designed to complement
a companion GWmodel study, which focuses on basic and robust GW models.


title: Liquidation of an indivisible asset with independent investment

abstract:
  We provide an extension of the explicit solution of a mixed optimal
stopping-optimal stochastic control problem introduced by Henderson and Hobson.
The problem examines wether the optimal investment problem on a local
martingale financial market is affected by the optimal liquidation of an
independent indivisible asset. The indivisible asset process is defined by a
homogeneous scalar stochastic differential equation, and the investor's
preferences are defined by a general expected utility function. The value
function is obtained in explicit form, and we prove the existence of an optimal
stopping-investment strategy characterized as the limit of an explicit
maximizing strategy. Our approach is based on the standard dynamic programming
approach.


title:
The distribution of the quasispecies for a Moran model on the sharp peak
  landscape

abstract:
  We consider the Moran model on the sharp peak landscape, in the asymptotic
regime studied in [3], where a quasispecies is formed. We find explicitly the
distribution of this quasispecies.


title:
Gas structure inside dust cavities of transition disks: Oph IRS 48
  observed by ALMA

abstract:
  (Abridged) Transition disks are recognized by the absence of emission of
small dust grains inside a radius of up to several 10s of AUs. Due to the lack
of angular resolution and sensitivity, the gas content of such dust holes has
not yet been determined, but is of importance to constrain the mechanism
leading to the dust holes. Transition disks are thought to currently undergo
the process of dispersal, setting an end to the giant planet formation process.
  We present new high-resolution observations with the Atacama Large
Millimeter/ submillimeter Array (ALMA) of gas lines towards the transition disk
Oph IRS 48 previously shown to host a large dust trap. ALMA has detected the
$J=6-5$ line of $^{12}$CO and C$^{17}$O around 690 GHz (434 $\mu$m) at a
resolution of $\sim$0.25$''$ corresponding to $\sim$30 AU (FWHM). The observed
gas lines are used to set constraints on the gas surface density profile.
  New models of the physical-chemical structure of gas and dust in Oph IRS 48
are developed to reproduce the CO line emission together with the spectral
energy distribution (SED) and the VLT-VISIR 18.7 $\mu$m dust continuum images.
Integrated intensity cuts and the total spectrum from models having different
trial gas surface density profiles are compared to observations. Using the
derived surface density profiles, predictions for other CO isotopologues are
made, which can be tested by future ALMA observations of the object.
  The derived gas surface density profile points to the clearing of the cavity
by one or more massive planet/companion rather than just photoevaporation or
grain-growth.


title:
Importance of d-p Coulomb interaction for high T$_C$ cuprates and other
  oxides

abstract:
  Current theoretical studies of electronic correlations in transition metal
oxides typically only account for the local repulsion between d-electrons even
if oxygen ligand p-states are an explicit part of the effective Hamiltonian.
Interatomic interactions such as Upd between d- and (ligand) p-electrons, as
well as the local interaction between p-electrons, are neglected. Often, the
relative d-p orbital splitting has to be adjusted "ad hoc" on the basis of the
experimental evidence. By applying the merger of local density approximation
and dynamical mean field theory (LDA+DMFT) to the prototypical case of the
3-band Emery dp model for the cuprates, we demonstrate that, without any "ad
hoc" adjustment of the orbital splitting, the charge transfer insulating state
is stabilized by the interatomic interaction Upd. Our study hence shows how to
improve realistic material calculations that explicitly include the p-orbitals.


title: Observation of many-body long-range tunneling after a quantum quench

abstract:
  Quantum tunneling constitutes one of the most fundamental processes in
nature. We observe resonantly-enhanced long-range quantum tunneling in
one-dimensional Mott-insulating Hubbard chains that are suddenly quenched into
a tilted configuration. Higher-order many-body tunneling processes occur over
up to five lattice sites when the tilt per site is tuned to integer fractions
of the Mott gap. Starting from a one-atom-per-site Mott state the response of
the many-body quantum system is observed as resonances in the number of doubly
occupied sites and in the emerging coherence in momentum space. Second- and
third-order tunneling shows up in the transient response after the tilt, from
which we extract the characteristic scaling in accordance with perturbation
theory and numerical simulations.


title: The Cosmological Constant Problem and Re-interpretation of Time

abstract:
  We abandon the interpretation that time is a global parameter in quantum
mechanics, replace it by a quantum dynamical variable playing the role of time.
This operational re-interpretation of time provides a solution to the
cosmological constant problem. The expectation value of the zero-point energy
under the new time variable vanishes. The fluctuation of the vacuum energy as
the leading contribution to the gravitational effect gives a correct order to
the observed "dark energy". The "dark energy" as a mirage is always seen
comparable with the matter energy density by an observer using the internal
clock time. Conceptual consequences of the re-interpretation of time are also
discussed.


title: Stein manifolds M for which O(M) has the property {\Omega}-tilda

abstract:
  In this note, we consider the linear topological invariant {\Omega}-tilda for
Fr\'echet spaces of global analytic functions on Stein manifolds. We show that
O(M), for a Stein manifold M, enjoys the property {\Omega}-tilda if and only if
every compact subset of M lies in a relatively compact sublevel set of a
bounded plurisubharmonic function defined on M. We also look at some immediate
implications of this characterization.


title:
Modelling spectral and timing properties of accreting black holes: the
  hybrid hot flow paradigm

abstract:
  The general picture that emerged by the end of 1990s from a large set of
optical and X-ray, spectral and timing data was that the X-rays are produced in
the innermost hot part of the accretion flow, while the optical/infrared (OIR)
emission is mainly produced by the irradiated outer thin accretion disc. Recent
multiwavelength observations of Galactic black hole transients show that the
situation is not so simple. Fast variability in the OIR band, OIR excesses
above the thermal emission and a complicated interplay between the X-ray and
the OIR light curves imply that the OIR emitting region is much more compact.
One of the popular hypotheses is that the jet contributes to the OIR emission
and even is responsible for the bulk of the X-rays. However, this scenario is
largely ad hoc and is in contradiction with many previously established facts.
Alternatively, the hot accretion flow, known to be consistent with the X-ray
spectral and timing data, is also a viable candidate to produce the OIR
radiation. The hot-flow scenario naturally explains the power-law like OIR
spectra, fast OIR variability and its complex relation to the X-rays if the hot
flow contains non-thermal electrons (even in energetically negligible
quantities), which are required by the presence of the MeV tail in Cyg X-1. The
presence of non-thermal electrons also lowers the equilibrium electron
temperature in the hot flow model to <100 keV, making it more consistent with
observations. Here we argue that any viable model should simultaneously explain
a large set of spectral and timing data and show that the hybrid
(thermal/non-thermal) hot flow model satisfies most of the constraints.


title:
On Oscillations of Solutions of the Fourth-Order Thin Film Equation Near
  Heteroclinic Bifurcation Point

abstract:
  It is shown that solutions of the Cauchy for the fourth-order thin film
equation becomes non-oscillatory and non-sign-changing precisely at and above
the heteroclinic bifurcation point n=1.75987..., so that, possibly, these
solutions begin to coincide with nonnegative solutions of a standard and
well-known free-boundary problem.


title: An experimental proposal for a Gaussian amendable quantum channel

abstract:
  We propose a quantum optics experiment where a single two-mode Gaussian
entangled state is used for realizing the paradigm of an amendable Gaussian
channel recently presented in Phys. Rev. A, \textbf{87}, 062307 (2013).
Depending on the choice of the experimental parameters the entanglement of the
probe state is preserved or not and the relative map belongs or not to the
class of entanglement breaking channels. The scheme has been optimized to be as
simple as possible: it requires only a single active non-linear operation
followed by four passive beam-splitters. The effects of losses, detection
inefficiencies and statistical errors are also taken into account, proving the
feasibility of the experiment with current realistic resources.


title:
Gaussian approximations for stochastic systems with delay: chemical
  Langevin equation and application to a Brusselator system

abstract:
  We present a heuristic derivation of Gaussian approximations for stochastic
chemical reaction systems with distributed delay. In particular we derive the
corresponding chemical Langevin equation. Due to the non-Markovian character of
the underlying dynamics these equations are integro-differential equations, and
the noise in the Gaussian approximation is coloured. Following on from the
chemical Langevin equation a further reduction leads to the linear-noise
approximation. We apply the formalism to a delay variant of the celebrated
Brusselator model, and show how it can be used to characterise noise-driven
quasi-cycles, as well as noise-triggered spiking. We find surprisingly
intricate dependence of the typical frequency of quasi-cycles on the delay
period.


title:
The resurgence properties of the large order asymptotics of the
  Anger--Weber function II

abstract:
  In this paper, we derive a new representation for the Anger--Weber function,
employing the reformulation of the method of steepest descents by C. J. Howls
(Howls, Proc. R. Soc. Lond. A 439 (1992) 373--396). As a consequence of this
representation, we deduce a number of properties of the large order asymptotic
expansion of the Anger--Weber function, including explicit and realistic error
bounds, asymptotic approximations for the late coefficients, exponentially
improved asymptotic expansions, and the smooth transition of the Stokes
discontinuities.


title: Supersymmetric Black Holes in AdS4 from Very Special Geometry

abstract:
  Supersymmetric black holes in AdS spacetime are inherently interesting for
the AdS/CFT correspondence. Within a four dimensional gauged supergravity
theory coupled to vector multiplets, the only analytic solutions for regular,
supersymmetric, static black holes in AdS4 are those in the STU-model due to
Cacciatori and Klemm. We study a class of U(1)-gauged supergravity theories
coupled to vector multiplets which have a cubic prepotential, the scalar
manifold is then a very special Kahler manifold. When the resulting very
special Kahler manifold is a homogeneous space, we find analytic solutions for
static, supersymmetric AdS4 black holes with vanishing axions. The horizon
geometries of our solutions are constant curvature Riemann surfaces of
arbitrary genus.


title:
Some remarks about q-Chebyshev polynomials and q-Catalan numbers and
  related results

abstract:
  The moments of the Lucas polynomials and of the Chebyshev polynomials of the
first kind are (multiples of) central binomial coefficients and the moments of
the Fibonacci polynomials and of the Chebyshev polynomials of the second kind
are Catalan numbers. In this survey paper we present some generalizations of
these results together with various q-analogues.


title: Supertwistors and massive particles

abstract:
  In the (super)twistor formulation of massless (super)particle mechanics, the
mass-shell constraint is replaced by a "spin-shell" constraint from which the
spin content can be read off. We extend this formalism to massive
(super)particles (with N-extended spacetime supersymmetry) in three and four
space-time dimensions, explaining how the spin-shell constraints are related to
spin, and we use it to prove equivalence of the massive N=1 and BPS-saturated
N=2 superparticle actions. We also find the supertwistor form of the action for
"spinning particles" with N-extended worldline supersymmetry, massless in four
dimensions and massive in three dimensions, and we show how this simplifies
special features of the N=2 case.


title:
Constraints on a decomposed dark fluid with constant adiabatic sound
  speed by jointing the geometry test and growth rate after Planck data

abstract:
  In this paper, a unified dark fluid with constant adiabatic sound speed is
decomposed into cold dark matter interacting with vacuum energy. Based on
Markov chain Monte Carlo method, we constrain this model by jointing the
geometry and dynamical measurement. The geometry test includes cosmic microwave
background radiation from \textit{Planck}, baryon acoustic oscillation, and
type Ia supernovae; the dynamic measurement is $f\sigma_8(z)$ data points which
is obtained from the growth rate via redshift-space distortion, and
$\sigma_8(z)$ is the root-mean-square amplitude of the density contrast
$\delta$ at the comoving $8h^{-1}$ Mpc scale. The jointed constraint shows that
$\alpha$ = $ 0.000662_{- 0.000662}^{+ 0.000173}$ and $\sigma_8$ = $ 0.824_{-
0.0166}^{+ 0.0128}$. The CMB and matter power spectra are both similar for the
case of $\alpha=$ mean value and that of $\alpha=0$. However, the evolutionary
curves of $f\sigma_8(z)$ are different. This means that, to some extent, the
data points of the growth rate could break the degeneracy of the dark energy
models.


title: Some characterizations of almost limited sets and applications

abstract:
  Recently, J.X. Chen et al. introduced and studied the class of almost limited
sets in Banach lattices. In this paper we establish some characterizations of
almost limited sets in Banach lattices (resp. wDP* property of Banach
lattices), that generalize some results obtained by J.X. Chen et al.. Also, we
introduce and study the class of the almost limited operators, which maps the
closed unit bull of a Banach space to an almost limited subset of a Banach
lattice. Some results about the relationship between the class of almost
limited operators and that of limited (resp. L- and M-weakly compact, resp.
compact) operators are presented.


title: Exotic cluster structures on $SL_{5}$

abstract:
  A conjecture by Gekhtman, Shapiro and Vainshtein suggests a correspondence
between the Belavin - Drinfeld classification of solutions of the classical
Yang - Baxter equation and cluster structures on simple Lie groups. This paper
confirms the conjecture for $SL_{5}$. Given a Belavin - Drinfeld class, we
construct the corresponding cluster structure in
$\mathcal{O}\left(SL_{5}\right)$, and show that it satisfies all parts of the
conjecture.


title:
Ab initio Investigation on Hybrid Graphite-like Structure Made up of
  Silicene and Boron Nitride

abstract:
  In this work, we report our results on the geometric and electronic
properties of hybrid graphite-like structure made up of silicene and boron
nitride (BN) layers. We predict from our calculations that this hybrid bulk
system, with alternate layers of honeycomb silicene and BN, possesses physical
properties similar to those of bulk graphite. We observe that there exists a
weak van der Waals interaction between the layers of this hybrid system in
contrast to the strong inter-layer covalent bonds present in multi-layers of
silicene. Furthermore, our results for the electronic band structure and the
density of states show that it is a semi-metal and the dispersion around the
Fermi level (E_F) is parabolic in nature and thus the charge carriers in this
system behave as \textit{Nearly-Free Particle-Like}. These results indicate
that the electronic properties of the hybrid bulk system resemble closely those
of bulk graphite. Around E_F the electronic band structures have contributions
only from silicene layers and the BN layer act only as a buffer layer in this
hybrid system since it does not contribute to the electronic properties near
E_F. In case of bi-layers of silicene with a single BN layer kept in between,
we observe a linear dispersion around E_F similar to that of graphene. However,
the characteristic linear dispersion become parabola-like when the system is
subjected to a compression along the transverse direction. Our present
calculations show that the hybrid system based on silicon and BN can be a
possible candidate for two dimensional layered system akin to graphite and
multi-layers of graphene.


title: Localized patterns in periodically forced systems

abstract:
  Spatially localized, time-periodic structures are common in pattern-forming
systems, appearing in fluid mechanics, chemical reactions, and granular media.
We examine the existence of oscillatory localized states in a PDE model with
single frequency time dependent forcing, introduced in [20] as phenomenological
model of the Faraday wave experiment. In this study, we reduce the PDE model to
the forced complex Ginzburg-Landau equation in the limit of weak forcing and
weak damping. This allows us to use the known localized solutions found in [7].
We reduce the forced complex Ginzburg-Landau equation to the Allen-Cahn
equation near onset, obtaining an asymptotically exact expression for localized
solutions. We also extend this analysis to the strong forcing case recovering
Allen-Cahn equation directly without the intermediate step. We find excellent
agreement between numerical localized solutions of the PDE, localized solutions
of the forced complex Ginzburg-Landau equation, and the Allen-Cahn equation.
This is the first time that a PDE with time dependent forcing has been reduced
to the Allen-Cahn equation, and its localized oscillatory solutions
quantitatively studied. This paper is dedicated to the memory of Thomas
Wagenknecht.


title:
Landau-Lifshitz's conjecture about the motion of a quantum mechanical
  particle under the inverse square potential

abstract:
  Landau and Lifshitz [4, Section 35] conjectured that for an arbitrary $k\in
\mathbb{R}$, there exists the motion of a quantum mechanical particle under the
inverse square potential $k|x|^{-2}$, $x \in \mathbb{R}^3$. When $k$ is
negative and $| k |$ is very large, the inverse square potential becomes very
deep and generates the very strong attractive force, and hence a quantum
mechanical particle is likely to fall down to the origin (the center of the
inverse square potential). Therefore this conjecture (Landau-Lifshitz's
conjecture) seems to be wrong at first sight. We however prove
Landau-Lifshitz's conjecture by showing that there exists a selfadjoint
extension for the Schr\"odinger operator with the inverse square potential
$-\Delta+k|x|^{-2}$ in $\mathbb{R}^N\ (N\geq 2)$ and that the spectrum of the
selfadjoint extension is bounded below for an arbitrary $k\in \mathbb{R}$. We
thus give the affirmative and complete answer to Landau-Lifshitz's conjecture
in $\mathbb{R}^N\ (N\geq 2)$.


title: Top tautological group of $\mathcal M_{g,n}$

abstract:
  We describe the structure of the top tautological group in the cohomology of
the moduli space of smooth genus $g$ curves with $n$ marked points.


title:
Rho meson distribution amplitudes from QCD sum rules with nonlocal
  condensates

abstract:
  The leading-twist distribution amplitude for the longitudinal rho-meson was
studied using QCD Sum Rules with nonlocal condensates and a spectral density
which includes next-to-leading order radiative corrections. The obtained
profile is compared with results from standard QCD sum rules, lattice QCD,
holographic QCD, a light-front quark model, and the instanton liquid model.
Preliminary estimates for the first two moments of the transverse $\rho$-meson
distribute amplitude are also given.


title: Magnetic Doppler Imaging of He-strong star HD 184927

abstract:
  We have employed an extensive new timeseries of Stokes I and V spectra
obtained with the ESPaDOnS spectropolarimeter at the 3.6-m Canada-France-Hawaii
Telescope to investigate the physical parameters, chemical abundance
distributions and magnetic field topology of the slowly-rotating He-strong star
HD 184927. We infer a rotation period of 9.53071+-0.00120 from H-alpha, H-beta,
LSD magnetic measurements and EWs of helium lines. We used an extensive NLTE
TLUSTY grid along with the SYNSPEC code to model the observed spectra and find
a new value of luminosity. In this poster we present the derived physical
parameters of the star and the results of Magnetic Doppler Imaging analysis of
the Stokes I and V profiles. Wide wings of helium lines can be described only
under the assumption of the presence of a large, very helium-rich spot.