title: Heavy quarkonium production in a strong magnetic field

abstract:
  It is well known that in noncentral heavy-ion collisions a transient strong
magnetic field is generated in the direction perpendicular to the reaction
plane. The maximal strength of this field is estimated to be $eB \sim m^2_{\pi}
\sim 0.02 \text{GeV}^2$ at the RHIC and $eB \sim 15 m^2_{\pi} \sim 0.3
\text{GeV}^2$ at the LHC. We investigate the effects of a strong magnetic field
on $B$ and $D$ mesons, focusing on the changes of the energy levels and the
masses of the bound states. Using the Color Evaporation Model we discuss the
possible changes in the production of $J/\psi$ and $\Upsilon$.


title: Stream of asymmetric bubbles in a Hele-Shaw channel

abstract:
  Exact solutions are reported for a stream of asymmetric bubbles steadily
moving in a Hele-Shaw channel. From the periodicity along the streamwise
direction, the flow region is reduced to a rectangular unit cell containing one
bubble, which is conformally mapped to an annulus in an auxiliary complex
plane. Analytic expressions for the bubble shape as well as for the velocity
field are obtained in terms of the generalized Schwarz-Christoffel formula for
doubly connected domains.


title: Axisymmetric thermoelectroelastic analysis of a piezoelectric half-space

abstract:
  In this study, an analytical solution is presented for thermo-electro-elastic
analysis of piezoelectric semi-infinite bodies. For this purpose, governing
equations are derived for a transversely isotropic piezoelectric material under
axisymmetric thermo-electro-mechanical loading condition. A general closed form
analytical solution is presented for the complementary and particular parts of
the components of displacement vector and also electric potential function.
Then, boundary conditions are imposed and in that case an explicit solution is
obtained for piezoelectric semi-infinite bodies. Results show that when a
piezoelectric half-space is subjected to constant/ramp surface thermal loading
the maximum absolute value of radial stress occurs at the surface of the body.
Whereas, the maximum absolute value of stress in normal direction of the
half-space surface occurs not on the surface but somewhere near the surface of
the body. Moreover, the peak values for these stress curves in the case of
combined loadings are closest to the half space surface and the farthest in the
case of ramp decaying thermal loading. In contrast to the constant/ramp surface
thermal loading no clear maximum point for electric field distribution for the
case of combined loadings can be seen in the normal direction to the half-space
boundary.


title:
Does the Great Firewall really isolate the Chinese? Integrating access
  blockage with cultural factors to explain web user behavior

abstract:
  The dominant understanding of Internet censorship posits that blocking access
to foreign-based websites creates isolated communities of Internet users. We
question this discourse for its assumption that if given access people would
use all websites. We develop a conceptual framework that integrates access
blockage with social structures to explain web users' choices, and argue that
users visit websites they find culturally proximate and access blockage matters
only when such sites are blocked. We examine the case of China, where online
blockage is notoriously comprehensive, and compare Chinese web usage patterns
with those elsewhere. Analyzing audience traffic among the 1000 most visited
websites, we find that websites cluster according to language and geography.
Chinese websites constitute one cluster, which resembles other such
geo-linguistic clusters in terms of both its composition and degree of
isolation. Our sociological investigation reveals a greater role of cultural
proximity than access blockage in explaining online behaviors.


title:
Stable Estimation of a Covariance Matrix Guided by Nuclear Norm
  Penalties

abstract:
  Estimation of covariance matrices or their inverses plays a central role in
many statistical methods. For these methods to work reliably, estimated
matrices must not only be invertible but also well-conditioned. In this paper
we present an intuitive prior that shrinks the classic sample covariance
estimator towards a stable target. We prove that our estimator is consistent
and asymptotically efficient. Thus, it gracefully transitions towards the
sample covariance matrix as the number of samples grows relative to the number
of covariates. We also demonstrate the utility of our estimator in two standard
situations -- discriminant analysis and EM clustering -- when the number of
samples is dominated by or comparable to the number of covariates.


title: Is Quantum Gravity a Super-Quantum Theory?

abstract:
  We argue that quantum gravity should be a super-quantum theory, that is, a
theory whose non-local correlations are stronger than those of canonical
quantum theory. As a super-quantum theory, quantum gravity should display
distinct experimentally observable super-correlations of entangled stringy
states.


title: Approximate Distance Oracle with Constant Query Time

abstract:
  An approximate distance oracle is a succinct data structure that provides
fast answers to distance queries between any two nodes. In this paper we
consider approximate distance oracles for general undirected graphs with
non-negative edge weights with constant query time. We present a distance
oracle of size O(k n^{1+1/k}), with 2k-1 stretch and O(1) query time. This
improves the O(log{k}) query time of Wulff-Nilsen's distance oracle [SODA '13],
which in turn improved the O(k) query time of Thorup and Zwick's distance
oracle [J. ACM '05].


title: Higgs search at ATLAS

abstract:
  In this paper the results of Higgs searches at the ATLAS experiment,
operating at the LHC, are summarised. The results are based on data samples
corresponding to an integrated luminosity of up to 20.7 fb-1 at a
centre-of-mass energy of 8 TeV and 4.6 fb-1 at 7 TeV. The observation of a
Higgs boson is established. The mass of the new boson is measured to be 125.5
+/- 0.2 (stat) +0.5-0.6 (syst) GeV, and the ratio of the observed number of
events and expected from a Standard Model Higgs Boson is compatible with unity,
mu = 1.30 +/- 0.13 (stat) +/- 0.14 (sys). The spin and parity properties as
well as the couplings structure are compatible with those predicted for a
Standard Model Higgs Boson. No evidence of further Higgs states is found.


title:
Transcritical flow of a stratified fluid over topography: analysis of
  the forced Gardner equation

abstract:
  Transcritical flow of a stratified fluid past a broad localised topographic
obstacle is studied analytically in the framework of the forced extended
Korteweg--de Vries (eKdV), or Gardner, equation. We consider both possible
signs for the cubic nonlinear term in the Gardner equation corresponding to
different fluid density stratification profiles. We identify the range of the
input parameters: the oncoming flow speed (the Froude number) and the
topographic amplitude, for which the obstacle supports a stationary localised
hydraulic transition from the subcritical flow upstream to the supercritical
flow downstream. Such a localised transcritical flow is resolved back into the
equilibrium flow state away from the obstacle with the aid of unsteady coherent
nonlinear wave structures propagating upstream and downstream. Along with the
regular, cnoidal undular bores occurring in the analogous problem for the
single-layer flow modeled by the forced KdV equation, the transcritical
internal wave flows support a diverse family of upstream and downstream wave
structures, including solibores, rarefaction waves, reversed and trigonometric
undular bores, which we describe using the recent development of the nonlinear
modulation theory for the (unforced) Gardner equation. The predictions of the
developed analytic construction are confirmed by direct numerical simulations
of the forced Gardner equation for a broad range of input parameters.


title:
Linear Reduced-Rank Interference Suppression for DS-UWB Systems Using
  Switched Approximations of Adaptive Basis Functions

abstract:
  In this work, we propose a novel low-complexity reduced-rank scheme and
consider its application to linear interference suppression in direct-sequence
ultra-wideband (DS-UWB) systems. Firstly, we investigate a generic reduced-rank
scheme that jointly optimizes a projection vector and a reduced-rank filter by
using the minimum mean-squared error (MMSE) criterion. Then a low-complexity
scheme, denoted switched approximation of adaptive basis functions (SAABF), is
proposed. The SAABF scheme is an extension of the generic scheme, in which the
complexity reduction is achieved by using a multi-branch framework to simplify
the structure of the projection vector. Adaptive implementations for the SAABF
scheme are developed by using least-mean squares (LMS) and recursive
least-squares (RLS) algorithms. We also develop algorithms for selecting the
branch number and the model order of the SAABF scheme. Simulations show that in
the scenarios with severe inter-symbol interference (ISI) and multiple access
interference (MAI), the proposed SAABF scheme has fast convergence and
remarkable interference suppression performance with low complexity.


title: Dimensions of Imaginary Root Spaces of Hyperbolic Kac--Moody Algebras

abstract:
  We discuss the known results and methods for determining root multiplicities
for hyperbolic Kac--Moody algebras.


title: Splitting trees with neutral mutations at birth

abstract:
  We consider a population model where individuals behave independently from
each other and whose genealogy is described by a chronological tree called
splitting tree. The individuals have i.i.d. (non-exponential) lifetime
durations and give birth at constant rate to clonal or mutant children in an
infinitely many alleles model with neutral mutations. First, to study the
allelic partition of the population, we are interested in its frequency
spectrum, which, at a fixed time, describes the number of alleles carried by a
given number of individuals and with a given age. We compute the expected value
of this spectrum and obtain some almost sure convergence results thanks to
classical properties of Crump-Mode-Jagers (CMJ) processes counted by random
characteristics. Then, by using multitype CMJ-processes, we get asymptotic
properties about the number of alleles that have undergone a fixed number of
mutations with respect to the ancestral allele of the population.


title:
Effects of local dissipation profiles on magnetized accretion disk
  spectra

abstract:
  We present spectral calculations of non-LTE accretion disk models appropriate
for high luminosity stellar mass black hole X-ray binary systems. We first use
a dissipation profile based on scaling the results of shearing box simulations
of Hirose et al. (2009) to a range of annuli parameters. We simultaneously
scale the effective temperature, orbital frequency and surface density with
luminosity and radius according to the standard \alpha-model (Shakura &
Sunyaev, 1973). This naturally brings increased dissipation to the disk surface
layers (around the photospheres) at small radii and high luminosities. We find
that the local spectrum transitions directly from a modified black body to a
saturated Compton scattering spectrum as we increase the effective temperature
and orbital frequency while decreasing midplane surface density. Next, we
construct annuli models based on the parameters of a L/L_Edd=0.8 disk orbiting
a 6.62 solar mass black hole using two modified dissipation profiles that
explicitly put more dissipation per unit mass near the disk surface. The new
dissipation profiles are qualitatively similar to the one found by Hirose et
al. (2009), but produce strong near power-law spectral tails. Our models also
include physically motivated magnetic acceleration support based once again on
scaling the Hirose et al. (2009) results. We present three full-disk spectra
each based on one of the dissipation prescriptions. Our most aggressive
dissipation profile results in a disk spectrum that is in approximate
quantitative agreement with certain observations of the steep power law (SPL)
spectral states from some black hole X-ray binaries.


title: A Mining-Based Compression Approach for Constraint Satisfaction Problems

abstract:
  In this paper, we propose an extension of our Mining for SAT framework to
Constraint satisfaction Problem (CSP). We consider n-ary extensional
constraints (table constraints). Our approach aims to reduce the size of the
CSP by exploiting the structure of the constraints graph and of its associated
microstructure. More precisely, we apply itemset mining techniques to search
for closed frequent itemsets on these two representation. Using Tseitin
extension, we rewrite the whole CSP to another compressed CSP equivalent with
respect to satisfiability. Our approach contrast with previous proposed
approach by Katsirelos and Walsh, as we do not change the structure of the
constraints.


title: A Hierarchical Finite Element Method for Quantum Field Theory

abstract:
  We study a model of scalar quantum field theory in which space-time is a
discrete set of points obtained by repeatedly subdividing a triangle into three
triangles at the centroid. By integrating out the field variable at the
centroid we get a renormalized action on the original triangle. The exact
renormalization map between the angles of the triangles is obtained as well. A
fixed point of this map happens to be the cotangent formula of Finite Element
Method which approximates the Laplacian in two dimensions.


title: Microwave spectroscopy of vortex dynamics in ortho-II YBa2Cu3O6.52

abstract:
  We present measurements of the vortex-state surface impedance, Z_s = R_s + i
X_s, of a high quality, ortho-II-ordered single crystal of the cuprate high
temperature superconductor YBa2Cu3O6.52 (T_c = 59K). Measurements have been
made at four microwave frequencies (\omega/2\pi = 2.64, 4.51, 9.12 and 13.97
GHz), for magnetic fields ranging from 0 to 7 T. From these data we obtain the
field, frequency and temperature dependence of the vortex viscosity, pinning
constant, depinning frequency and flux-flow resistivity. The vortex viscosity,
\eta(\omega,T), has a surprisingly strong frequency dependence and bears a
striking resemblance to the zero-field quasiparticle conductivity,
\sigma_qp(\omega,T), suggesting that the dominant dissipative mechanism for the
flux lines is induced electric fields coupling to bulk, long-lived d-wave
quasiparticles outside the vortex cores. This is in sharp contrast to the
conventional Bardeen-Stephen picture, in which dissipation takes place inside
quasi-normal vortex cores. The strong frequency dependence of the vortex
viscosity in the microwave range requires us to treat it as a complex response
function, with an imaginary part that is predicted to contribute to the
apparent pinning force on the vortices. Measurements of the frequency
dependence of the pinning force confirm that this term is present, and in a
form consistent with the requirements of causality. At low temperatures the
flux-flow resistivity, \rho_ff \propto 1/\eta, has the form \rho_ff(T) = \rho_0
+ \rho_1 \ln(1/T), reminiscent of the DC resistivity of cuprates in the
pseudogap regime.


title:
On the relationships between Fourier - Stieltjes coefficients and
  spectra of measures

abstract:
  We construct examples of uncountable compact subsets of complex numbers with
the property that any Borel measure on the circle group taking values of its
Fourier coefficients from this set has natural spectrum. For measures with
Fourier coefficients tending to 0 we construct tho open set with this property.


title: On the spatial dynamics of the solution to the stochastic heat equation

abstract:
  We consider the solution of $\partial_t u=\partial_x^2 u+\partial_x\partial_t
B,\,(x,t)\in R\times(0,\infty)$, subject to $u(x,0)=0,\,x\in R$, where $B$ is a
Brownian sheet. We show that $u$ also satisfies $\partial_x^2 u
+[\,(-\partial_t^2)^{1/2}+\sqrt{2}\partial_x(-\partial_t^2)^{1/4}\,]\,u^a=
\partial_x\partial_t{\tilde B}$ in $R\times(0,\infty)$ where $u^a$ stands for
the extension of $u(x,t)$ to $(x,t)\in R^2$ which is antisymmetric in $t$ and
$\tilde{B}$ is another Brownian sheet. The new SPDE allows us to prove the
strong Markov property of the pair $(u,\partial_x u)$ when seen as a process
indexed by $x\ge x_0$, $x_0$ fixed, taking values in a state space of functions
in $t$. The method of proof is based on enlargement of filtration and we
discuss how our method could be applied to other quasi-linear SPDEs.


title: A Discrete and Coherent Basis of Intertwiners

abstract:
  We construct a new discrete basis of 4-valent SU(2) intertwiners. This basis
possesses both the advantage of being discrete, while at the same time
representing accurately the classical degrees of freedom; hence it is coherent.
The closed spin network amplitude obtained from these intertwiners depends on
twenty spins and can be evaluated by a generalization of the Racah formula for
an arbitrary graph. The asymptotic limit of these amplitudes is found. We give,
for the first time, the asymptotics of 15j symbols in the real basis.
Remarkably it gives a generalization of the Regge action to twisted geometries.


title:
Probing the tunneling site of electrons in strong field enhanced
  ionization of molecules

abstract:
  Molecules show a much increased multiple ionization rate in a strong laser
field as compared to atoms of similar ionization energy. A widely accepted
model attributes this to the action of the joint fields of the adjacent ionic
core and the laser on its neighbor inside the same molecule. The underlying
physical picture for the enhanced ionization is that the up-field atom that
gets ionized. However, this is still debated and remains unproven. Here we
report an experimental verification of this long-standing prediction. This is
accomplished by probing the two-site double ionization of ArXe, where the
instantaneous field direction at the moment of electron release and the
emission direction of the correlated ionizing center are measured by detecting
the recoil sum- and relative-momenta of the fragment ions. Our results
unambiguously prove the intuitive picture of the enhanced multielectron
dissociative ionization of molecules and clarify a long-standing controversy.


title:
Riding the crest of the altmetrics wave: How librarians can help prepare
  faculty for the next generation of research impact metrics

abstract:
  As scholars migrate into online spaces like Mendeley, blogs, Twitter, and
more, they leave new traces of once-invisible interactions like reading,
saving, discussing, and recommending. Observing these traces can inform new
metrics of scholarly influence and impact -- so-called "altmetrics."
Stakeholders in academia are beginning to discuss how and where altmetrics can
be useful towards evaluating a researcher's academic contribution. As this
interest grows, libraries are in a unique position to help support an informed
dialog on campus. We suggest that librarians can provide this support in three
main ways: informing emerging conversations with the latest research,
supporting experimentation with emerging altmetrics tools, and engaging in
early altmetrics education and outreach. We include examples and lists of
resources to help librarians fill these roles.


title: Spokes cluster: The search for the quiescent gas

abstract:
  Context. Understanding the role of fragmentation is one of the most important
current questions of star formation. To better understand the process of star
and cluster formation, we need to study in detail the physical structure and
properties of the parental molecular cloud. The Spokes cluster, or NGC 2264 D,
is a rich protostellar cluster where previous N2H+(1-0) observations of its
dense cores presented linewidths consistent with supersonic turbulence.
However, the fragmentation of the most massive of these cores appears to have a
scale length consistent with that of the thermal Jeans length, suggesting that
turbulence was not dominant. Aims. These two results probe different density
regimes. Our aim is to determine if there is subsonic or less-turbulent gas
(than previously reported) in the Spokes cluster at higher densities. Methods.
We present APEX N2H+(3-2) and N2D+(3-2) observations of the NGC2264-D region to
measure the linewidths and the deuteration fraction of the higher density gas.
The critical densities of the selected transitions are more than an order of
magnitude higher than that of N2H+(1-0). Results. We find that the N2H+(3-2)
and N2D+(3-2) emission present significantly narrower linewidths than the
emission from N2H+(1-0) for most cores. In two of the spectra, the nonthermal
component is close (within 1-sigma) to the sound speed. In addition, we find
that the three spatially segregated cores, for which no protostar had been
confirmed show the highest levels of deuteration. Conclusions. These results
show that the higher density gas, probed with N2H+ and N2D+(3-2), reveals more
quiescent gas in the Spokes cluster than previously reported. More high-angular
resolution interferometric observations using high-density tracers are needed
to truly assess the kinematics and substructure within NGC2264-D. (Abridged)


title:
Computational error estimates for Born-Oppenheimer molecular dynamics
  with nearly crossing potential surfaces

abstract:
  The difference of the values of observables for the time-independent
Schroedinger equation, with matrix valued potentials, and the values of
observables for ab initio Born-Oppenheimer molecular dynamics, of the ground
state, depends on the probability to be in excited states and the
electron/nuclei mass ratio. The paper first proves an error estimate (depending
on the electron/nuclei mass ratio and the probability to be in excited states)
for this difference of microcanonical observables, assuming that molecular
dynamics space-time averages converge, with a rate related to the maximal
Lyapunov exponent. The error estimate is uniform in the number of particles and
the analysis does not assume a uniform lower bound on the spectral gap of the
electron operator and consequently the probability to be in excited states can
be large. A numerical method to determine the probability to be in excited
states is then presented, based on Ehrenfest molecular dynamics and stability
analysis of a perturbed eigenvalue problem.


title: The study of high pressure structural stability of CeO2 nanoparticles

abstract:
  In situ high pressure XRD diffraction and Raman spectroscopy have been
performed on 12 nm CeO2 nanoparticles. Surprisingly, under quasihydrostatic
condition, 12 nm CeO2 nanoparticles maintain the fluorite-type structure in the
whole pressure range (0-51 GPa) during the experiments, much more stable than
the bulk counterpart (PT=31 GPa). In contrast, they experienced phase
transition at pressure as low as 26 GPa under non-hydrostatic condition
(adopting CsCl as pressure medium). Additionally, 32-36 nm CeO2 nanoparticles
exhibit an onset pressure of phase transition at 35GPa under quasihydrostatic
condition, and this onset pressure is much lower than our result. Further
analysis shows both the experimental condition (i.e., quasihydrostatic or
non-hydrostatic) and grain size effect have a significant impact on the high
pressure behaviors of CeO2 nanomaterials.


title: In-vivo magnetic resonance imaging of hyperpolarized silicon particles

abstract:
  Silicon-based micro and nanoparticles have gained popularity in a wide range
of biomedical applications due to their biocompatibility and biodegradability
in-vivo, as well as a flexible surface chemistry, which allows drug loading,
functionalization and targeting. Here we report direct in-vivo imaging of
hyperpolarized 29Si nuclei in silicon microparticles by MRI. Natural physical
properties of silicon provide surface electronic states for dynamic nuclear
polarization (DNP), extremely long depolarization times, insensitivity to the
in-vivo environment or particle tumbling, and surfaces favorable for
functionalization. Potential applications to gastrointestinal, intravascular,
and tumor perfusion imaging at sub-picomolar concentrations are presented.
These results demonstrate a new background-free imaging modality applicable to
a range of inexpensive, readily available, and biocompatible Si particles.


title: Strategy-Proof Facility Location for Concave Cost Functions

abstract:
  We consider k-Facility Location games, where n strategic agents report their
locations on the real line, and a mechanism maps them to k facilities. Each
agent seeks to minimize his connection cost, given by a nonnegative increasing
function of his distance to the nearest facility. Departing from previous work,
that mostly considers the identity cost function, we are interested in
mechanisms without payments that are (group) strategyproof for any given cost
function, and achieve a good approximation ratio for the social cost and/or the
maximum cost of the agents.
  We present a randomized mechanism, called Equal Cost, which is group
strategyproof and achieves a bounded approximation ratio for all k and n, for
any given concave cost function. The approximation ratio is at most 2 for Max
Cost and at most n for Social Cost. To the best of our knowledge, this is the
first mechanism with a bounded approximation ratio for instances with k > 2
facilities and any number of agents. Our result implies an interesting
separation between deterministic mechanisms, whose approximation ratio for Max
Cost jumps from 2 to unbounded when k increases from 2 to 3, and randomized
mechanisms, whose approximation ratio remains at most 2 for all k. On the
negative side, we exclude the possibility of a mechanism with the properties of
Equal Cost for strictly convex cost functions. We also present a randomized
mechanism, called Pick the Loser, which applies to instances with k facilities
and n = k+1 agents, and for any given concave cost function, is strongly group
strategyproof and achieves an approximation ratio of 2 for Social Cost.


title: Online Learning in a Contract Selection Problem

abstract:
  In an online contract selection problem there is a seller which offers a set
of contracts to sequentially arriving buyers whose types are drawn from an
unknown distribution. If there exists a profitable contract for the buyer in
the offered set, i.e., a contract with payoff higher than the payoff of not
accepting any contracts, the buyer chooses the contract that maximizes its
payoff. In this paper we consider the online contract selection problem to
maximize the sellers profit. Assuming that a structural property called ordered
preferences holds for the buyer's payoff function, we propose online learning
algorithms that have sub-linear regret with respect to the best set of
contracts given the distribution over the buyer's type. This problem has many
applications including spectrum contracts, wireless service provider data plans
and recommendation systems.


title: Superconductivity Induced by Breaking Te2 Dimers of AuTe2

abstract:
  Mineral calaverite AuTe2 is a layered compound with an incommensurately
modulated structure. The modulation is characterized by the formation of
molecular-like Te2 dimers. We have found that the breaking of Te2 dimers that
occurs in Au1-xPtxTe2 results in the emergence of superconductivity at Tc = 4.0
K.


title: The Empirical Implications of Rank in Bimatrix Games

abstract:
  We study the structural complexity of bimatrix games, formalized via rank,
from an empirical perspective. We consider a setting where we have data on
player behavior in diverse strategic situations, but where we do not observe
the relevant payoff functions. We prove that high complexity (high rank) has
empirical consequences when arbitrary data is considered. Additionally, we
prove that, in more restrictive classes of data (termed laminar), any
observation is rationalizable using a low-rank game: specifically a zero-sum
game. Hence complexity as a structural property of a game is not always
testable. Finally, we prove a general result connecting the structure of the
feasible data sets with the highest rank that may be needed to rationalize a
set of observations.


title: On the Archimedean characterization of parabolas

abstract:
  Archimedes knew that the area between a parabola and any chord $AB$ on the
parabola is four thirds of the area of triangle $\Delta ABP$ where P is the
point on the parabola at which the tangent is parallel to $AB$. We consider
whether this property (and similar ones) characterizes parabolas. We present
five conditions which are necessary and sufficient for a strictly convex curve
in the plane to be a parabola.


title:
An Efficient Method for Optimizing RFID Reader Deployment and Energy
  Saving

abstract:
  The rapid proliferation of Radio Frequency IDentification (RFID) systems
realizes integration of physical world with the cyber ones. One of the most
promising is the Internet of Things (IoT), a vision in which the Internet
extends into our daily activities through wireless networks of uniquely
identifiable objects. Given that modern RFID systems are being deployed in
large-scale for different applications, without optimizing reader's
distribution, many of the readers will be redundant, resulting waste of energy.
Additionally, eliminating redundant eaders can also decrease probability of
reader collisions, as a result, enhancing system performance and efficiency. In
this paper, an overlap aware (OA) technique is proposed for eliminating
redundant readers. The OA is a distributed approach, which does not need to
collect global information for centralizing control, aims to detect maximum
amount of redundant readers could be safely removed or turned off with
preserving original RFID network coverage. A significant improvement of the OA
scheme is that the amount of "write-to-tag" operations could be largely reduced
during the redundant reader identification phase. In order to accurately
evaluate the performance of the proposed method, it was performed in a variety
of scenarios. The experiment results show that the proposed method can provide
reliable performance with detecting higher redundancy and has lower algorithm
overheads as compared with several well known methods, such as the RRE, LEO,
the hybrid algorithm (LEO+RRE) and the DRRE.


title:
Top-quark mass measurement in events with jets and missing transverse
  energy using the full CDF data set

abstract:
  We present a measurement of the top-quark mass using the full data set of
Tevatron $\sqrt{s} = 1.96$ TeV proton-antiproton collisions recorded by the CDF
II detector, corresponding to an integrated luminosity of \invfb{8.7}. The
analysis uses events with one semileptonic $t$ or $\bar{t}$ decay, but without
detection of the electron or muon. We select events with significant missing
transverse energy and multiple jets. We veto events containing identified
electrons or muons. We obtain distributions of the top-quark masses and the
invariant mass of the two jets from $W$-boson decays from data and compare
these to templates derived from signal and background samples to extract the
top-quark mass and the energy scale of the calorimeter jets with {\it in situ}
calibration. A likelihood fit of the templates from signal and background
events to the data yields the top-quark mass, $\mtop =
\gevcc{\measStatSyst{173.93}{1.64}{0.87}}$. This result is the most precise
measurement to date of the mass of the top quark in this event topology.


title: On cubic elliptic varieties

abstract:
  Let X->P^(n-1) be an elliptic fibration obtained by resolving the
indeterminacy of the projection of a cubic hypersurface Y of P^(n+1) from a
line L not contained in Y. We prove that the Mordell-Weil group of the elliptic
fibration is finite if and only if the Cox ring of X is finitely generated. We
also provide a presentation of the Cox ring of X when it is finitely generated.


title: Beam energy dependence of the viscous damping of anisotropic flow

abstract:
  The flow harmonics $v_{2,3}$ for charged hadrons, are studied for a broad
range of centrality selections and beam collision energies in Au+Au
($\sqrt{s_{NN}}= 7.7 - 200$ GeV) and Pb+Pb ($\sqrt{s_{NN}}= 2.76$ TeV)
collisions. They validate the characteristic signature expected for the system
size dependence of viscous damping at each collision energy studied. The
extracted viscous coefficients, that encode the magnitude of the ratio of shear
viscosity to entropy density $\eta/s$, are observed to decrease to an apparent
minimum as the collision energy is increased from $\sqrt{s_{NN}}= 7.7$ to
approximately 62.4 GeV; thereafter, they show a slow increase with
$\sqrt{s_{NN}}$ up to 2.76 TeV. This pattern of viscous damping provides the
first experimental constraint for $\eta/s$ in the temperature-baryon chemical
potential ($T, \mu_B$) plane, and could be an initial indication for decay
trajectories which lie close to the critical end point in the phase diagram for
nuclear matter.


title:
Hilbert-P\'olya Conjecture, Zeta-Functions and Bosonic Quantum Field
  Theories

abstract:
  The original Hilbert and P\'olya conjecture is the assertion that the
non-trivial zeros of the Riemann zeta function can be the spectrum of a
self-adjoint operator. So far no such operator was found. However the
suggestion of Hilbert and P\'olya, in the context of spectral theory, can be
extended to approach other problems and so it is natural to ask if there is a
quantum mechanical system related to other sequences of numbers which are
originated and motivated by Number Theory.
  In this paper we show that the functional integrals associated with a
hypothetical class of physical systems described by self-adjoint operators
associated with bosonic fields whose spectra is given by three different
sequence of numbers cannot be constructed. The common feature of the sequence
of numbers considered here, which causes the impossibility of zeta
regularization, is that the various Dirichlet series attached to such sequences
- such as those which are sums over "primes" of $(\mathrm{norm} \ P)^{-s}$ have
a natural boundary, i.e., they cannot be continued beyond the line
$\mathrm{Re}(s)=0$. The main argument is that once the regularized determinant
of a Laplacian is meromorphic in $s$, it follows that the series considered
above cannot be a regularized determinant. In other words we show that the
generating functional of connected Schwinger functions of the associated
quantum field theories cannot be constructed.


title:
Thermoelectric Transport Coefficients for Massless Dirac Electrons in
  Quantum Limit

abstract:
  We perform an analytic calculation of thermoelectric transport coefficients
for massless Dirac electrons using the approach based on the Kubo--St\v{r}eda
formula and generalized Mott's relation. The main focus of the letter is made
on the properties of the Nernst coefficient in the vicinity of the Dirac point
in quantum limit. We calculate magnetic field and temperature dependencies of
the Nernst coefficient and compare our results with recent experiments in
$\alpha$-(BEDT-TTF)$_{2}$I$_{3}$ organic conductor. We argue that the Zeeman
splitting is important to understand the experimental data at high magnetic
fields.


title:
Holomorphic isometry from a Kahler manifold into a product of complex
  projective manifolds

abstract:
  We study the global property of local holomorphic isometric mappings from a
class of Kahler manifolds into a product of projective algebraic manifolds with
induced Fubini-Study metrics, where isometric factors are allowed to be
negative.


title: Augmenting Operating Systems With the GPU

abstract:
  The most popular heterogeneous many-core platform, the CPU+GPU combination,
has received relatively little attention in operating systems research. This
platform is already widely deployed: GPUs can be found, in some form, in most
desktop and laptop PCs. Used for more than just graphics processing, modern
GPUs have proved themselves versatile enough to be adapted to other
applications as well. Though GPUs have strengths that can be exploited in
systems software, this remains a largely untapped resource. We argue that
augmenting the OS kernel with GPU computing power opens the door to a number of
new opportunities. GPUs can be used to speed up some kernel functions, make
other scale better, and make it feasible to bring some computation-heavy
functionality into the kernel. We present our framework for using the GPU as a
co-processor from an OS kernel, and demonstrate a prototype in Linux.


title: Observation of elastic collisions between lithium atoms and calcium ions

abstract:
  We observed elastic collisions between laser-cooled fermionic lithium atoms
and calcium ions at the energy range from 100 mK to 3 K. Lithium atoms in an
optical-dipole trap were transported to the center of the ion trap using an
optical tweezer technique, and a spatial overlap of the atoms and ions was
realized in order to observe the atom-ion interactions. The elastic scattering
rate was determined from the decay of atoms due to elastic collisions with
ions. The collision-energy dependence of the elastic scattering cross-section
was consistent with semi-classical collision theory.


title:
featureCounts: An efficient general-purpose program for assigning
  sequence reads to genomic features

abstract:
  Next-generation sequencing technologies generate millions of short sequence
reads, which are usually aligned to a reference genome. In many applications,
the key information required for downstream analysis is the number of reads
mapping to each genomic feature, for example to each exon or each gene. The
process of counting reads is called read summarization. Read summarization is
required for a great variety of genomic analyses but has so far received
relatively little attention in the literature. We present featureCounts, a read
summarization program suitable for counting reads generated from either RNA or
genomic DNA sequencing experiments. featureCounts implements highly efficient
chromosome hashing and feature blocking techniques. It is considerably faster
than existing methods (by an order of magnitude for gene-level summarization)
and requires far less computer memory. It works with either single or
paired-end reads and provides a wide range of options appropriate for different
sequencing applications. featureCounts is available under GNU General Public
License as part of the Subread (http://subread.sourceforge.net) or Rsubread
(http://www.bioconductor.org) software packages.


title:
Full-sky formulae for weak lensing power spectra from total angular
  momentum method

abstract:
  We systematically derive full-sky formulae for the weak lensing power spectra
generated by scalar, vector and tensor perturbations from the total angular
momentum (TAM) method. Based on both the geodesic and geodesic deviation
equations, we first give the gauge-invariant expressions for the deflection
angle and Jacobi map as observables of the CMB lensing and cosmic shear
experiments. We then apply the TAM method, originally developed in the
theoretical studies of CMB, to a systematic derivation of the angular power
spectra. The TAM representation, which characterizes the total angular
dependence of the spatial modes projected along a line-of-sight, can carry all
the information of the lensing modes generated by scalar, vector, and tensor
metric perturbations. This greatly simplifies the calculation, and we present a
complete set of the full-sky formulae for angular power spectra in both the
E-/B-mode cosmic shear and gradient-/curl-mode lensing potential of deflection
angle. Based on the formulae, we give illustrative examples of non-vanishing
B-mode cosmic shear and curl-mode of deflection angle in the presence of the
vector and tensor perturbations, and explicitly compute the power spectra.


title: Algebraic K-theory of Geometric Groups

abstract:
  Let $\Gamma$ be a geometrically finite group of finite asymptotic dimension
and let $R$ be a noetherian ring of finite homological dimension. The main
result of the paper is that the integral K-theoretic assembly map for the group
ring $R[\Gamma]$ is an isomorphism. We also include partial results for larger
classes of geometric groups.


title: DANSSino: a pilot version of the DANSS neutrino detector

abstract:
  DANSSino is a reduced pilot version of a solid-state detector of reactor
antineutrinos (to be created within the DANSS project and installed under the
industrial 3 GW(th) reactor of the Kalinin Nuclear Power Plant -- KNPP).
Numerous tests performed at a distance of 11 m from the reactor core
demonstrate operability of the chosen design and reveal the main sources of the
background. In spite of its small size (20x20x100 ccm), the pilot detector
turned out to be quite sensitive to reactor antineutrinos, detecting about 70
IBD events per day with the signal-to-background ratio about unity.


title: Quality Sensitive Price Competition in Spectrum Oligopoly

abstract:
  We investigate a spectrum oligopoly where primary users allow secondary
access in lieu of financial remuneration. Transmission qualities of the
licensed bands fluctuate randomly. Each primary needs to select the price of
its channel with the knowledge of its own channel state but not that of its
competitors. Secondaries choose among the channels available on sale based on
their states and prices. We formulate the price selection as a non-cooperative
game and prove that a symmetric Nash equilibrium (NE) strategy profile exists
uniquely. We explicitly compute this strategy profile and analytically and
numerically evaluate its efficiency. Our structural results provide certain key
insights about the unique symmetric NE.


title: The quantitative Morse theorem

abstract:
  In this paper, we give a proof of the quantitative Morse theorem stated by
{Y. Yomdin} in \cite{Y1}. The proof is based on the quantitative Sard theorem,
the quantitative inverse function theorem and the quantitative Morse lemma.


title: Finite-Size Effects in Dynamics: Critical vs Coarsening Phenomena

abstract:
  Finite-size effects in systems with diverging characteristic lengthscale have
been addressed via state-of-the-art Monte Carlo and molecular dynamics
simulations of various models exhibiting solid-solid, liquid-liquid and
vapor-liquid transitions. Our simulations, combined with the appropriate
application of finite-size scaling theory, confirm various non-trivial
singularities in equilibrium dynamic critical phenomena and non-equilibrium
domain coarsening phenomena, as predicted by analytical theories. We
convincingly demonstrate that the finite-size effects in the domain growth
problems, with conserved order parameter dynamics, is weak and universal,
irrespective of the transport mechanism. This result is strikingly different
from the corresponding effects in critical dynamics. In critical phenomena,
difference in finite-size effects between statics and dynamics is also
discussed.


title:
Approximate Congestion Games for Load Balancing in Distributed
  Environment

abstract:
  The use of game theoretic models has been quite successful in describing
various cooperative and non-cooperative optimization problems in networks and
other domains of computer systems. In this paper, we study an application of
game theoretic models in the domain of distributed system, where nodes play a
game to balance the total processing loads among themselves. We have used
congestion gaming model, a model of game theory where many agents compete for
allocating resources, and studied the existence of Nash Equilibrium for such
types of games. As the classical congestion game is known to be PLS-Complete,
we use an approximation, called the \epsilon-Congestion game, which converges
to \epsilon-Nash equilibrium within finite number of steps under selected
conditions. Our focus is to define the load balancing problem using the model
of \epsilon-congestion games, and finally provide a greedy algorithm for load
balancing in distributed systems. We have simulated our proposed system to show
the effect of \epsilon-congestion game, and the distribution of load at
equilibrium state.


title:
Existence of affine pavings for varieties of partial flags associated to
  nilpotent elements

abstract:
  The flag variety of a complex reductive linear algebraic group G is by
definition the quotient G/B by a Borel subgroup. It can be regarded as the set
of Borel subalgebras of Lie(G). Given a nilpotent element e in Lie(G), one
calls Springer fiber the subvariety formed by the Borel subalgebras which
contain e. Springer fibers have in general a complicated structure (not
irreducible, singular). Nevertheless, a theorem by C. De Concini, G. Lusztig,
and C. Procesi asserts that, when G is classical, a Springer fiber can always
be paved by finitely many subvarieties isomorphic to affine spaces. In this
paper, we study varieties generalizing the Springer fibers to the context of
partial flag varieties, that is, subvarieties of the quotient G/P by a
parabolic subgroup (instead of a Borel subgroup). The main result of the paper
is a generalization of De Concini, Lusztig, and Procesi's theorem to this
context.


title: Analytical Evaluation of Coverage-Oriented Femtocell Network Deployment

abstract:
  This paper proposes a coverage-oriented femtocell network deployment scheme,
in which the femtocell base stations (BSs) can decide whether to be active or
inactive depending on their distances from the macrocell BSs. Specifically, as
the areas close to the macrocell BSs already have satisfactory cellular
coverage, the femtocell BSs located inside such areas are kept to be inactive.
Thus, all the active femtocells are located in the poor macrocell coverage
areas. Based on a stochastic geometric framework, the coverage probability can
be analyzed with tractable results. Surprisingly, the results show that the
proposed scheme, although with a lower defacto femtocell density, can achieve
better coverage performance than that keeping all femtocells in the entire
network to be active. The analytical results further identify the achievable
optimal performance of the new scheme, which provides mobile operators a
guideline for femtocell deployment and operation.


title: Quantum enhanced metrology in the presence of arbitrary loss

abstract:
  We introduce the concept of entanglement enhanced interferometry from the
viewpoint of the detected photons. The standard quantum limit is achieved when
sequentially detected photons are assumed to be in an uncorrelated product
state. However when we access the correlations between the detected photons
that existed before the interferometer it becomes clear that entanglement
enhanced measurement beyond the quantum limit could be achieved independent of
loss. We describe possible realisations of this post-measurement entanglement
detection using a small array of spin photon entangling gates. We then describe
a proof of principle experiment using only linear optics resources.


title: Symmetry in Distributed Storage Systems

abstract:
  The max-flow outer bound is achievable by regenerating codes for functional
repair distributed storage system. However, the capacity of exact repair
distributed storage system is an open problem. In this paper, the linear
programming bound for exact repair distributed storage systems is formulated. A
notion of symmetrical sets for a set of random variables is given and
equalities of joint entropies for certain subsets of random variables in a
symmetrical set is established. Concatenation coding scheme for exact repair
distributed storage systems is proposed and it is shown that concatenation
coding scheme is sufficient to achieve any admissible rate for any exact repair
distributed storage system. Equalities of certain joint entropies of random
variables induced by concatenation scheme is shown. These equalities of joint
entropies are new tools to simplify the linear programming bound and to obtain
stronger converse results for exact repair distributed storage systems.


title:
Fine-scale structure of the quasar 3C 279 Measured with 1.3 mm very long
  baseline interferometry

abstract:
  We report results from 5-day VLBI observations of the well-known quasar 3C
279 at 1.3 mm (230 GHz) in 2011. The measured nonzero closure phases on
triangles including stations in Arizona, California and Hawaii indicate that
the source structure is spatially resolved. We find an unusual inner jet
direction at scales of $\sim$1 parsec extending along the northwest-southeast
direction (PA = $127^{\circ}\pm3^{\circ}$), as opposed to other (previously)
reported measurements on scales of a few parsecs showing inner jet direction
extending to the southwest. The 1.3 mm structure corresponds closely with that
observed in the central region of quasi-simultaneous super-resolution VLBA
images at 7 mm. The closure phase changed significantly on the last day when
compared with the rest of observations, indicating that the inner jet structure
may be variable on daily timescales. The observed new direction of the inner
jet shows inconsistency with the prediction of a class of jet precession
models. Our observations indicate a brightness temperature of $\sim
8\times10^{10}$ K in the 1.3 mm core, much lower than that at centimeter
wavelengths. Observations with better uv coverage and sensitivity in the coming
years will allow the discrimination between different structure models and will
provide direct images of the inner regions of the jet with 20--30 $\mu$as (5--7
light months) resolution.


title:
Giant dipole resonance width as a probe for nuclear deformation at
  finite excitation

abstract:
  The systematic study of the correlation between the experimental giant dipole
resonance (GDR) width and the average deformation <\beta> of the nucleus at
finite excitation is presented for the mass region A ~ 59 to 208. We show that
the width of the GDR (\Gamma) and the quadrupole deformation of the nucleus do
not follow a linear relation, as predicted earlier, due to the GDR induced
quadrupole moment and the correlation also depends on the mass of the nuclei.
The different empirical values of <\beta> extracted from the experimental GDR
width match exceptionally well with the thermal shape fluctuation model. As a
result, this universal correlation between <\beta> and \Gamma provides a direct
experimental probe to determine the nuclear deformation at finite temperature
and angular momentum in the entire mass region.


title:
Intrinsic electron spin relaxation due to the D'yakonov-Perel' mechanism
  in monolayer MoS$_2$

abstract:
  Intrinsic electron spin relaxation due to the D'yakonov-Perel' mechanism is
studied in monolayer Molybdenum Disulphide. An intervalley in-plane spin
relaxation channel is revealed due to the opposite effective magnetic fields
perpendicular to the monolayer Molybdenum Disulphide plane in the two valleys
together with the intervalley electron-phonon scattering. The intervalley
electron-phonon scattering is always in the weak scattering limit, which leads
to a rapid decrease of the in-plane spin relaxation time with increasing
temperature. A decrease of the in-plane spin relaxation time with the increase
of the electron density is also shown.


title: Entropy-driven aggregation in multilamellar membranes

abstract:
  Membrane-fluctuation-induced attraction between ligand--receptor sites
binding neighboring membranes is studied using meshless membrane simulations
and the Weil--Farago two-dimensional lattice model. For the adhesion sites
binding two membranes, this entropic interaction is too weak by itself for the
adhesion sites to form a large stable domain. However, it is found that this
attraction is enhanced sufficiently to induce large domains either when the
sites bind three or more neighboring membranes together or have anchors that
harden surrounding membranes. The latter effect is understood by the
Asakura--Oosawa type of effective potential in the depletion theory.


title: Quantized space-time and its influences on some physical problems

abstract:
  Based on the idea of quantized space-time of Snyder, we derive new
generalized uncertainty principle and new modified density of states.
Accordingly we discuss the influences of the modified density of states on some
physical quantities and laws. In addition we analyzed the exact solution of the
harmonic oscillator in Snyder's quantized space-time.


title:
Generalized Diversity-Multiplexing Tradeoff of Half-Duplex Relay
  Networks

abstract:
  Diversity-multiplexing trade-off has been studied extensively to quantify the
benefits of different relaying strategies in terms of error and rate
performance. However, even in the case of a single half-duplex relay, which
seems fully characterized, implications are not clear. When all channels in the
system are assumed to be independent and identically fading, a fixed schedule
where the relay listens half of the total duration for communication and
transmits the second half combined with quantize-map-and-forward relaying
(static QMF) is known to achieve the full-duplex performance [1]. However, when
there is no direct link between the source and the destination, a dynamic
decode-and-forward (DDF) strategy is needed [2]. It is not clear which one of
these two conclusions would carry to a less idealized setup, where the direct
link can be neither as strong as the other links nor fully non-existent.
  In this paper, we provide a generalized diversity-multiplexing trade-off for
the half-duplex relay channel which accounts for different channel strengths
and recovers the two earlier results as two special cases. We show that these
two strategies are sufficient to achieve the diversity-multiplexing trade-off
across all channel configurations, by characterizing the best achievable
trade-off when channel state information (CSI) is only available at the
receivers (CSIR). However, for general relay networks we show that a
generalization of these two schemes through a dynamic QMF strategy is needed to
achieve optimal performance.


title: A Construction of the Best Fractal Approximation

abstract:
  In this paper we present a method for constructing the continuous best
fractal approximation in the space of bounded functions. We construct the
finite-dimensional subspace of the space of bounded functions whose base
consists of the continuous fractal functions, and propose how to find the best
approximation of given continuous function by element of the constructed space.


title:
The Swift Gamma-Ray Burst redshift distribution: selection biases or
  rate evolution at high-z?

abstract:
  We employ realistic constraints on selection effects to model the Gamma-Ray
Burst (GRB) redshift distribution using {\it Swift} triggered redshift samples
acquired from optical afterglows and the TOUGH survey. Models for the Malmquist
bias, redshift desert, and the fraction of afterglows missing because of host
galaxy dust extinction, are used to show how the "true" GRB redshift
distribution is distorted to its presently observed biased distribution. Our
analysis, which accounts for the missing fraction of redshifts in the two data
subsets, shows that a combination of selection effects (both instrumental and
astrophysical) can describe the observed GRB redshift distribution. The
observed distribution supports the case for dust extinction as the dominant
astrophysical selection effect that shapes the redshift distribution.


title: A simple method to downscale daily wind statistics to hourly wind data

abstract:
  Wind is the principal driver in the wind erosion models. The hourly wind
speed data were generally required for precisely wind erosion modeling. In this
study, a simple method to generate hourly wind speed data from daily wind
statistics (daily average and maximum wind speeds together or daily average
wind speed only) was established.
  A typical windy location with 3285 days (9 years) measured hourly wind speed
data were used to validate the downscaling method. The results showed that the
overall agreement between observed and simulated cumulative wind speed
probability distributions appears excellent, especially for the wind speeds
greater than 5 m s-1 range (erosive wind speed). The results further revealed
that the values of daily average erosive wind power density (AWPD) calculated
from generated wind speeds fit the counterparts computed from measured wind
speeds well with high models' efficiency (Nash-Sutcliffe coefficient). So that
the hourly wind speed data can be predicted from daily average and maximum wind
speed data or only daily average wind speed data, respectively. Further studies
are needed to examine the findings for inter-site wind data.


title: Phonon-mediated Superconductivity in Silicene

abstract:
  We predict that electron-doped silicene is a good two-dimensional
electron-phonon superconductor under biaxial tensile strain by first-principles
calculations within rigid band approximation. Superconductivity transition
temperature of electron-doped silicene can be increased to be above 10 K by 5%
tensile strain. Band structures, phonon dispersive relations, and Eliashberg
functions are calculated for detailed analysis. The strong interaction between
acoustic phonon modes normal to the silicene plane and the increasing
electronic states around the Fermi level induced by tensile strain is mainly
responsible for the enhanced critical temperature.


title:
Elastic scattering of surface states on three-dimensional topological
  insulators

abstract:
  Topological insulators as new type of quantum matter materials are
characterized by a full insulating gap in the bulk and gapless edge/surface
states which are protected by time-reversal symmetry. We propose the
interference patterns caused by elastic scattering of defects or impurities are
dominated by surface states at the extremal points on the constant energy
contour. Within such formalism, we summarize our recent theoretical
investigations on elastic scattering of topological surface states by various
imperfections, including the non-magnetic impurities, magnetic impurities,
step-edges, and various other defects, in comparison with recent related
experiments in typical topological materials such as BiSb alloys, Bi$_2$Te$_3$
and Bi$_2$Se$_3$ crystals.


title: L2-estimates on p-convex Riemannian manifolds

abstract:
  In this paper, we establish various L2-estimates for the exterior
differential operator on p-convex Riemannian manifolds in the sense of Harvey
and Lawson. As geometric applications, we prove vanishing and finiteness
results for the de Rham cohomology groups.


title:
VLBA Multi-frequency Polarimetric imaging of Radio-loud Broad Absorption
  Line Quasars

abstract:
  We conducted the first multi-frequency polarimetric imaging of four broad
absorption line (BAL) quasars using Very Long Baseline Array at milli-arcsecond
resolutions to investigate the inclination of the non-thermal jet and test the
hypothesis that radio sources in BAL quasars are still young. Among these four
sources, J0928+446, J1018+0530, and J1405+4056 show one-sided structures in
parsec scales, and polarized emission detected in the core. These
characteristics are consistent with those of blazars. We set constraints on
viewing angles to $<$66 deg for these jets, in the framework of a Doppler
beaming effect. J1159+0112 exhibits an unpolarized gigahertz peaked spectrum
component and several discrete blobs with steep spectra on both sides of the
central component across $\sim$1 kpc. These properties are consistent with
those of young radio sources. We discuss the structures of jets and AGN wind.


title: Cosmological Zitterbewegung

abstract:
  We describe a new phenomenon of zitterbewegung of a free Dirac particle in
cosmological spacetimes. Unlike the similar effect theorized by Schrodinger in
1930, the cosmological zitterbewegung is a real, physically attainable effect,
which originates from the mixing of positive and negative frequency modes of a
field operator in cosmological spacetimes. We briefly discuss the potential for
observing this effect in laboratory experiments with trapped ions.


title:
Form factor approach to diagonal finite volume matrix elements in
  Integrable QFT

abstract:
  We derive an exact formula for finite volume excited state mean values of
local operators in 1+1 dimensional Integrable QFT with diagonal scattering. Our
result is a non-trivial generalization of the LeClair-Mussardo series, which is
a form factor expansion for finite size ground state mean values.


title:
Radio-Continuum Study of the Nearby Sculptor Group Galaxies. Part 2: NGC
  55 at {\lambda}=20, 13, 6 and 3 cm

abstract:
  A series of new radio-continuum ({\lambda}=20, 13, 6 and 3 cm) mosaic images
focused on the NGC55 galactic system were produced using archived observational
data from the Australia Telescope Compact Array. These new images are both very
sensitive (down to rms=33 {\mu}Jy) and feature high angular resolution (down to
<4"). Using these newly created images, 66 previously unidentified discrete
sources are identified. Of these sources, 46 were classified as background
sources, 11 as HII regions and 6 as supernova remnant candidates. This
relatively low number of SNR candidates detected coupled with the low number of
large HII regions is consistent with the estimated low star formation rate of
the galaxy at 0.06 solar masses per year. Our spectral index map shows that the
core of galaxy appears to have a shallow spectral index between {\alpha} = -0.2
and -0.4. This indicates that the core of the galaxy is a region of high
thermal radiation output.


title:
On the Role of Common Codewords in Quadratic Gaussian Multiple
  Descriptions Coding

abstract:
  This paper focuses on the problem of $L-$channel quadratic Gaussian multiple
description (MD) coding. We recently introduced a new encoding scheme in [1]
for general $L-$channel MD problem, based on a technique called `Combinatorial
Message Sharing' (CMS), where every subset of the descriptions shares a
distinct common message. The new achievable region subsumes the most well known
region for the general problem, due to Venkataramani, Kramer and Goyal (VKG)
[2]. Moreover, we showed in [3] that the new scheme provides a strict
improvement of the achievable region for any source and distortion measures for
which some 2-description subset is such that the Zhang and Berger (ZB) scheme
achieves points outside the El-Gamal and Cover (EC) region. In this paper, we
show a more surprising result: CMS outperforms VKG for a general class of
sources and distortion measures, which includes scenarios where for all
2-description subsets, the ZB and EC regions coincide. In particular, we show
that CMS strictly extends VKG region, for the $L$-channel quadratic Gaussian MD
problem for all $L\geq3$, despite the fact that the EC region is complete for
the corresponding 2-descriptions problem. Using the encoding principles
derived, we show that the CMS scheme achieves the complete rate-distortion
region for several asymmetric cross-sections of the $L-$channel quadratic
Gaussian MD problem, which have not been considered earlier.


title:
Delay and Doppler Spreads of Non-Stationary Vehicular Channels for
  Safety Relevant Scenarios

abstract:
  Vehicular communication channels are characterized by a non-stationary time-
and frequency-selective fading process due to rapid changes in the environment.
The non-stationary fading process can be characterized by assuming local
stationarity for a region with finite extent in time and frequency. For this
finite region the wide-sense stationarity and uncorrelated-scattering (WSSUS)
assumption holds approximately and we are able to calculate a time and
frequency dependent local scattering function (LSF). In this paper, we estimate
the LSF from a large set of measurements collected in the DRIVEWAY'09
measurement campaign, which focuses on scenarios for intelligent transportation
systems. We then obtain the time-frequency-varying power delay profile (PDP)
and the time-frequency-varying Doppler power spectral density (DSD) from the
LSF. Based on the PDP and the DSD, we analyze the time-frequency-varying root
mean square (RMS) delay spread and the RMS Doppler spread. We show that the
distribution of these channel parameters follows a bi-modal Gaussian mixture
distribution. High RMS delay spread values are observed in situations with rich
scattering, while high RMS Doppler spreads are obtained in drive-by scenarios.


title:
Microscopic and self-consistent description for neutron halo in deformed
  nuclei

abstract:
  A deformed relativistic Hartree-Bogoliubov theory in continuum has been
developed for the study of neutron halos in deformed nuclei and the halo
phenomenon in deformed weakly bound nuclei is investigated. Magnesium and neon
isotopes are studied and some results are presented for the deformed
neutron-rich and weakly bound nuclei 44Mg and 36Ne. The core of the former
nucleus is prolate, but the halo has a slightly oblate shape. This indicates a
decoupling of the halo orbitals from the deformation of the core. The generic
conditions for the existence of halos in deformed nuclei and for the occurrence
of this decoupling effect are discussed.


title: Negative-frequency dispersive wave generation in quadratic media

abstract:
  We show that the extremely blue-shifted dispersive wave emitted in Kerr media
owing to the coupling with the negative-frequency branch [Phys. Rev. Lett. {\bf
108}, 253901 (2012)] can be observed in quadratic media via second-harmonic
generation. Not only such phenomenon is thus independent on the specific
nonlinear mechanism, but it is shown to occur regardless of the fact that the
process is pumped by a pulse which exhibits soliton-like features or,
viceversa, undergoes wave-breaking. A simple unified formula gives the
frequencies of the emitted dispersive waves in both cases.


title: Maxwell's equal area law for charged Anti-deSitter black holes

abstract:
  In this paper we present the construction of the Maxwell equal area law in
the Hawking temperature graph for a charged black hole in Anti-deSitter
background. We are able to find exact solution for the corresponding isotherm
and entropies for "gaseous" (large) black holes and "liquid" (near-extremal)
black holes. Isothermal construction removes the unphysical, negative heat
capacity, regions. Furthermore, extremal black holes turn out to be dual to
"un-shrinkable" molecules of Van der Waals real fluid, which may explain their
thermodynamical stability.


title: Description of Euler bricks using Fibonacci's identity

abstract:
  We show how the Fibonacci's identity is used to obtain Euler bricks. Also,we
put forward the relation between Fibonacci's identity and Euler's formula,
which provides the description of Euler's bricks with noninteger spatial
diagonal. Finally,we establish a relation between the Euler bricks with integer
and noninteger spatial diagonals.


title: AW(k)-Type Curves According to the Bishop Frame

abstract:
  In this study, we consider AW(k)-type curves according to the Bishop Frame in
Euclidean space E^3. We give the relations between the Bishop curvatures k_1,
k_2 of a curve in E^3.


title:
On Asymptotically Distribution Free Tests with Parametric Hypothesis for
  Ergodic Diffusion Processes

abstract:
  We consider the problem of the construction of the asymptotically
distribution free test by the observations of ergodic diffusion process. It is
supposedd that under the basic hypothesis the trend coefficient depends on the
finite dimensional parameter and we study the Cramer-von Mises type statistics.
The underlying statistics depends on the deviation of the local time estimator
from the invariant density with parameter replaced by the maximum likelihood
estimator. We propose a linear transformation which yields the convergence of
the test statistics to the integral of Wiener process. Therefore the test based
on this statistics is asymptotically distribution free.


title: Stable control of 10 dB two-mode squeezed vacuum states of light

abstract:
  Continuous variable entanglement is a fundamental resource for many quantum
information tasks. Important protocols like superactivation of zero-capacity
channels and finite-size quantum cryptography that provides security against
most general attacks, require about 10 dB two-mode squeezing. Additionally,
stable phase control mechanisms are necessary but are difficult to achieve
because the total amount of optical loss to the entangled beams needs to be
small. Here, we experimentally demonstrate a control scheme for two-mode
squeezed vacuum states at the telecommunication wavelength of 1550 nm. Our
states exhibited an Einstein-Podolsky-Rosen covariance product of 0.0309 \pm
0.0002, where 1 is the critical value, and a Duan inseparability value of 0.360
\pm 0.001, where 4 is the critical value. The latter corresponds to 10.45 \pm
0.01 dB which reflects the average non-classical noise suppression of the two
squeezed vacuum states used to generate the entanglement. With the results of
this work demanding quantum information protocols will become feasible.


title:
Transfer Learning for Content-Based Recommender Systems using Tree
  Matching

abstract:
  In this paper we present a new approach to content-based transfer learning
for solving the data sparsity problem in cases when the users' preferences in
the target domain are either scarce or unavailable, but the necessary
information on the preferences exists in another domain. We show that training
a system to use such information across domains can produce better performance.
Specifically, we represent users' behavior patterns based on topological graph
structures. Each behavior pattern represents the behavior of a set of users,
when the users' behavior is defined as the items they rated and the items'
rating values. In the next step we find a correlation between behavior patterns
in the source domain and behavior patterns in the target domain. This mapping
is considered a bridge between the two domains. Based on the correlation and
content-attributes of the items, we train a machine learning model to predict
users' ratings in the target domain. When we compare our approach to the
popularity approach and KNN-cross-domain on a real world dataset, the results
show that on an average of 83$%$ of the cases our approach outperforms both
methods.


title:
Nanoscale order in the frustrated mixed conductor
  La$_{5.4}WO$_{12-\delta}$

abstract:
  We report a comprehensive investigation of the average and local structure of
La$_{5.4}$WO$_{12-\delta}$, which has excellent mixed proton, electron and
oxide ion conduction suitable for device applications. Synchrotron X-ray and
neutron powder diffraction show that a cubic fluorite supercell describes the
average structure, with highly disordered lanthanum and oxide positions. On
average the tungsten sites are six-fold coordinated, and we detect a trace
(4.4(2) %) of anti-site disorder. In addition to sharp Bragg reflections,
strong diffuse neutron scattering is observed, which hints at short-range
order. We consider plausible local configurations, and show that the defect
chemistry implies a simple 'chemical exchange' interaction that favours ordered
WO6 octahedra. Our local model is confirmed by synchrotron x-ray pair
distribution function analysis and EXAFS experiments performed at the La K and
W L3-edges. We show that ordered domains of around ca. 3.5 nm are found,
implying that mixed conduction in La$_{5.4}$WO$_{12-\delta}$? is associated
with a defective glassy-like anion sublattice. The origins of this ground state
are proposed to lie in the non-bipartite nature of the fcc lattice and the
pairwise interactions which link the orientation of neighbouring octahedral WO6
sites. This 'function through frustration' could provide a means of designing
new mixed conductors.


title:
Type II-Plateau supernova radiation: dependencies on progenitor and
  explosion properties

abstract:
  We explore the properties of Type II-Plateau (II-P) supernovae (SNe) together
with their red-supergiant (RSG) star progenitors. Using MESA STAR, we modulate
the parameters (e.g., mixing length, overshoot, rotation, metallicity) that
control the evolution of a 15Msun main-sequence star to produce a variety of
physical pre-SN models and SN II-P ejecta. We extend previous modeling of SN
II-P radiation to include photospheric and nebular phases, as well as
multi-band light curves and spectra. Our treatment does not assume local
thermodynamic equilibrium, is time dependent, treats explicitly the effects of
line blanketing, and incorporates non-thermal processes. We find that the color
properties of SNe II-P require large model atoms for FeI and FeII, much larger
than adopted in Dessart & Hillier (2011). The color properties also imply RSG
progenitors of limited extent (~500Rsun) --- larger progenitor stars produce a
SN II-P radiation that remains too blue for too long. This finding calls for a
reduction of RSG radii, perhaps through a strengthening of convective energy
transport in RSG envelopes. Increased overshoot and rotation reduce the ratio
of ejecta to helium-core mass, similarly to an increase in main-sequence mass,
and thus complicate the inference ofprogenitor masses. In contrast to the great
sensitivity on progenitor radius, SN II-P color evolution appears insensitive
to variations in explosion energy. Finally, we document the numerous SN II-P
signatures that vary with progenitor metallicity, revealing their potential for
metallicity determinations in the nearby and distant Universe.


title:
Evidence of hydrodynamic and subdiffusive motion of tracers in a
  viscoelastic medium

abstract:
  We propose a theoretical model which relies on the generalized Langevin
equation and may account for various dynamical features of the thermal motion
of organelles, vesicles or macromolecules in viscoelastic media such as polymer
networks. In particular, we consider inertial and hydrodynamic effects at short
times, subdiffusive scaling at intermediate times, and eventually optical
trapping at long times. Simple analytical formulas for the mean square
displacement and velocity auto-correlation function are derived. The developed
theory is applied to the analysis of fifty-second long trajectories of
micron-sized spherical tracers in actin gels that were acquired at one
microsecond temporal resolution by using optical tweezers single-particle
tracking. For the first time, both the subdiffusive scaling and hydrodynamic
effects are observed within a single experiment and accurately described by a
minimal phenomenological model.


title:
A Witness Extraction Technique by Proof Normalization Based on
  Interactive Realizability

abstract:
  We present a new set of reductions for derivations in natural deduction that
can extract witnesses from closed derivations of simply existential formulas in
Heyting Arithmetic (HA) plus the Excluded Middle Law restricted to simply
existential formulas (EM1), a system motivated by its interest in proof mining.
  The reduction we have for classical logic are quite different from all
existing ones. They are inspired by the informal idea of learning by making
falsifiable hypothesis and checking them, and by the interactive realizability
interpretation. We extract the witnesses directly from derivations in HA+EM1 by
reduction, without encoding derivations by a realizability interpretation.


title:
A zero-mode mechanism for spontaneous symmetry breaking in a turbulent
  von K\'arm\'an flow

abstract:
  We suggest that the dynamical spontaneous symmetry breaking reported in a
turbulent swirling flow at $Re=40~000$ by Cortet et al., Phys. Rev. Lett., 105,
214501 (2010) can be described through a continuous one parameter family
transformation (amounting to a phase shift) of steady states and could be the
analogue of the Goldstone mode of the vertical translational symmetry in an
ideal system. We investigate a possible mechanism of emergence of such
spontaneous symmetry breaking in a toy model of our out-equilibrium system,
derived from its equilibrium counterpart. We show that the stationary states
are solution of a linear differential equation. For a specific value of the
Reynolds number, they are subject to a spontaneous symmetry breaking through a
zero-mode mechanism. These zero-modes obey a Beltrami property and their
spontaneous fluctuations can be seen as the "phonon of turbulence".


title: Electric Charges and Magnetic Monopoles in Gravity's Rainbow

abstract:
  In this work, we explore the possibility that quantum fluctuations induce an
electric or magnetic charge or both, in the context of Gravity's Rainbow. A
semi-classical approach is adopted, where the graviton one-loop contribution to
a classical energy in a background spacetime is computed through a variational
approach with Gaussian trial wave functionals. The energy density of the
graviton one-loop contribution, in this context, acts as a source for the
electric/magnetic charge. The ultraviolet (UV) divergences, which arise
analyzing this procedure, are kept under control with the help of an
appropriate choice of the Rainbow's functions. In this way we avoid the
introduction of any regularization/renormalization scheme. A comparison with
the observed data lead us to determine the size of the electron and of the
magnetic monopole which appear to be of Planckian size. Both results seem to be
of the same order for a Schwarzschild and a de Sitter background, respectively.
Estimates on the magnetic monopole size have been done with the help of the
Dirac quantization procedure. We find that the monopole radius is larger than
the electron radius. Even in this case the ratio between the electric and
magnetic monopole radius appears to be of the same order for both geometries.


title:
Roles of oxygen vacancies on ferromagnetism in Ni doped In2O3: A hybrid
  functional study

abstract:
  The roles of oxygen vacancies on the electronic and magnetic properties of Ni
doped In$_2$O$_3$ have been studied by first-principles calculations based on
hybrid functional theory. Our results predict that the Ni-doped In$_2$O$_3$
system displays a ferromagnetic semiconducting character. However, the presence
of oxygen vacancies results in antiferromagnetic coupling between the
neighboring Ni pair bridged by an oxygen vacancy. The antiferromagnetic
coupling is found to arise from the predominant role of superexchange due to
the strong Ni 3d-O 2p hybridization. Consequently, the oxygen vacancies play a
key role in the lower saturation magnetization of Ni:In$_2$O$_3$
polycrystalline sample, as observed in experiments.


title: The Gravitational Wave Spectrum from Cosmological B-L Breaking

abstract:
  Cosmological B-L breaking is a natural and testable mechanism to generate the
initial conditions of the hot early universe. If B-L is broken at the grand
unification scale, the false vacuum phase drives hybrid inflation, ending in
tachyonic preheating. The decays of heavy B-L Higgs bosons and heavy neutrinos
generate entropy, baryon asymmetry and dark matter and also control the
reheating temperature. The different phases in the transition from inflation to
the radiation dominated phase produce a characteristic spectrum of
gravitational waves. We calculate the complete gravitational wave spectrum due
to inflation, preheating and cosmic strings, which turns out to have several
features. The production of gravitational waves from cosmic strings has large
uncertainties, with lower and upper bounds provided by Abelian Higgs strings
and Nambu-Goto strings, implying \Omega_GW h^2 ~ 10^{-13} - 10^{-8}, much
larger than the spectral amplitude predicted by inflation. Forthcoming
gravitational wave detectors such as eLISA, advanced LIGO, ET, and BBO/DECIGO
will reach the sensitivity needed to test the predictions from cosmological B-L
breaking.


title: Every Separable Metrizable Space has a Proper Dyadic Subbase

abstract:
  The notions of a proper dyadic subbase and an independent subbase was
introduced by H. Tsuiki to investigate in {0, 1, bot}-sequence codings of
topological spaces. We show that every separable metrizable space has a proper
dyadic subbase whose restriction to the perfect set defined by the
Cantor-Bendixson theorem forms an independent subbase of the restricted space.


title: Rational curves and lines on the moduli space of stable bundles

abstract:
  Fix a smooth projetive curve $\mathcal {C}$ of genus $g\geq 2$ and a line
bundle $\mathcal{L}$ on $\mathcal{C}$ of degree $d$. Let $M:=
\mathcal{SU}_{\mathcal{C}}(r, \mathcal{L})$ be the moduli space of stable
vector bundles on $\mathcal{C}$ of rank $r$ and with fixed determinant
$\mathcal{L}$. We prove that any rational curve on $M$ is a generalized Hecke
curve. Furthermore, we study the lines on $M$, and prove that $M$ is covered by
the lines when $(r, d)=r$; for the case $(r,d)<r$, the lines fill up a closed
subvariety of $M$, and we determine the number of its irreducible components
and the dimension of each irreducible component when $g>(r,d)+1$. Finally, we
prove that there are no $(1,0)$-stable (resp., $(0,1)$-stable) bundles for
$g=2$, $r=2$ and $d$ is odd as an application.


title:
Moebius invariant BFKL equation for the adjoint representation in N=4
  SUSY

abstract:
  It is shown that in the next-to-leading approximation of N=4 SUSY the BFKL
equation for two-gluon composite states in the adjoint representation of the
gauge group can be reduced to a form which is invariant under Moebius
transformation in the momentum space. The corresponding similarity
transformation of its integral kernel is constructed in an explicit way.


title:
Exhaustive Search for Small Dimension Recursive MDS Diffusion Layers for
  Block Ciphers and Hash Functions

abstract:
  This article presents a new algorithm to find MDS matrices that are well
suited for use as a diffusion layer in lightweight block ciphers. Using an
recursive construction, it is possible to obtain matrices with a very compact
description. Classical field multiplications can also be replaced by simple
F2-linear transformations (combinations of XORs and shifts) which are much
lighter. Using this algorithm, it was possible to design a 16x16 matrix on a
5-bit alphabet, yielding an efficient 80-bit diffusion layer with maximal
branch number.


title:
The Brownian motion as the limit of a deterministic system of
  hard-spheres

abstract:
  We provide a rigorous derivation of the brownian motion as the limit of a
deterministic system of hard-spheres as the number of particles $N$ goes to
infinity and their diameter $\varepsilon$ simultaneously goes to $0$, in the
fast relaxation limit $\alpha = N\varepsilon^{d-1}\to \infty $ (with a suitable
diffusive scaling of the observation time). As suggested by Hilbert in his
sixth problem, we rely on a kinetic formulation as an intermediate level of
description between the microscopic and the fluid descriptions: we use indeed
the linear Boltzmann equation to describe one tagged particle in a gas close to
global equilibrium. Our proof is based on the fundamental ideas of Lanford. The
main novelty here is the detailed study of the branching process, leading to
explicit estimates on pathological collision trees.


title:
Fundamental solutions and local solvability for nonsmooth H\"ormander's
  operators

abstract:
  We consider operators of the form $L=\sum_{i=1}^{n}X_{i}^{2}+X_{0}$ in a
bounded domain of R^p where X_0, X_1,...,X_n are nonsmooth H\"ormander's vector
fields of step r such that the highest order commutators are only H\"older
continuous. Applying Levi's parametrix method we construct a local fundamental
solution \gamma\ for L and provide growth estimates for \gamma\ and its first
derivatives with respect to the vector fields. Requiring the existence of one
more derivative of the coefficients we prove that \gamma\ also possesses second
derivatives, and we deduce the local solvability of L, constructing, by means
of \gamma, a solution to Lu=f with H\"older continuous f. We also prove
$C_{X,loc}^{2,\alpha}$ estimates on this solution.


title:
A return to strong radio flaring by Circinus X-1 observed with the Karoo
  Array Telescope test array KAT-7

abstract:
  Circinus X-1 is a bright and highly variable X-ray binary which displays
strong and rapid evolution in all wavebands. Radio flaring, associated with the
production of a relativistic jet, occurs periodically on a ~17-day timescale. A
longer-term envelope modulates the peak radio fluxes in flares, ranging from
peaks in excess of a Jansky in the 1970s to an historic low of milliJanskys
during the years 1994 to 2007. Here we report first observations of this source
with the MeerKAT test array, KAT-7, part of the pathfinder development for the
African dish component of the Square Kilometre Array (SKA), demonstrating
successful scientific operation for variable and transient sources with the
test array. The KAT-7 observations at 1.9 GHz during the period 13 December
2011 to 16 January 2012 reveal in temporal detail the return to the
Jansky-level events observed in the 1970s. We compare these data to
contemporaneous single-dish measurements at 4.8 and 8.5 GHz with the HartRAO
26-m telescope and X-ray monitoring from MAXI. We discuss whether the overall
modulation and recent dramatic brightening is likely to be due to an increase
in the power of the jet due to changes in accretion rate or changing Doppler
boosting associated with a varying angle to the line of sight.


title:
Hybrid functional with semi-empirical van der Waals study of native
  defects in hexagonal BN

abstract:
  The formation energies and transition energy levels of native defects in
hexagonal BN have been studied by first-principles calculations based on hybrid
density functional theory (DFT) together with an empirical dispersion
correction of Grimme's DFT-D2 method. Our calculated results predict that the
interstitial B is the most stable defect under N-rich and p-type conditions.
While the B vacancy and interstitial N become the dominate defects when the
electron chemical potential is near the conduction band maximum of host.
Nevertheless, these compensating defects would be inactive due to their ultra
deep ionization levels under both p- and n-type conditions.


title: The self fied effect on the power-law index of superconducting cables

abstract:
  It is shown that in the absence of inter-strand current redistribution the
self-field effect is to always increase the power-law index of the volt-ampere
characteristic and to decrease the temperature and magnetic field derivatives
of the critical current line. We show that the take-off limit of a strand in a
cable made of insulated strands is equal to that of a free strand due to a
compensation effect between the increase of the power-law index and the
decrease of the magnetic field derivative of the critical current.


title: Some Applications of the Extended Bendixson-Dulac Theorem

abstract:
  During the last years the authors have studied the number of limit cycles of
several families of planar vector fields. The common tool has been the use of
an extended version of the celebrated Bendixson-Dulac Theorem. The aim of this
work is to present an unified approach of some of these results, together with
their corresponding proofs. We also provide several applications.


title: On a mixed arithmetic-geometric mean inequality

abstract:
  We extend a result of Holland on a mixed arithmetic-geometric mean
inequality.


title:
Multiple Cover Calculation for the Unramified Compactification of the
  Moduli Space of Stable Maps

abstract:
  In this paper we compute the multiple cover Gromov-Witten integrals (analog
of the Aspinwall-Morrison formula) for the unramified compactification of the
moduli space of stable maps to an embedded $\PO$ in a Calabi-Yau threefold $X$
with the normal bundle $\mathcal{O}_{\PO}(-1) \bigoplus \mathcal{O}_{\PO}(-1)$.


title: On the distribution of Jacobi sums

abstract:
  Let $\mathbf{F}_q$ be a finite field of $q$ elements. For multiplicative
characters $\chi_1,\dots, \chi_m$ of $\mathbf{F}_q^\times$, we let
$J(\chi_1,\dots, \chi_m)$ denote the Jacobi sum. Nicholas Katz and Zhiyong
Zheng showed that for $m=2$, the normalized Jacobi sum
$q^{-1/2}J(\chi_1,\chi_2)$ ($\chi_1\chi_2$ nontrivial) is asymptotically
equidistributed on the unit circle as $q\to \infty$, when $\chi_1$ and $\chi_2$
run through all nontrivial multiplicative characters of $\mathbf{F}_q^\times$.
In this paper, we show a similar property for $m\ge 2$. More generally, we show
that the normalized Jacobi sum $q^{-(m-1)/2}J(\chi_1,\dots,\chi_m)$
($\chi_1\dotsm \chi_m$ nontrivial) is asymptotically equidistributed on the
unit circle, when $\chi_1,\dots, \chi_m$ run through arbitrary sets of
nontrivial multiplicative characters of $\mathbf{F}_q^\times$ with two of the
sets being sufficiently large. The case $m=2$ answers a question of
Shparlinski.


title: On Tense MV-algebras

abstract:
  The main aim of this article is to study tense MV-algebras which are just
MV-algebras with new unary operations $G$ and $H$ which express a universal
time quantifiers. Tense MV-algebras were introduced by D. Diagonescu and G.
Georgescu. Using a new notion of an fm-function between MV-algebras we
\zruseno{will prove} \zmena{settle a half of their Open problem about
representation for some classes of tense MV-algebras, i.e., we show} that any
tense semisimple MV-algebra is induced by a time frame analogously to classical
works in this field of logic. As a by-product we obtain a new characterization
of extremal states on MV-algebras.


title:
Probabilistic Nearest Neighbor Queries on Uncertain Moving Object
  Trajectories

abstract:
  Nearest neighbor (NN) queries in trajectory databases have received
significant attention in the past, due to their application in spatio-temporal
data analysis. Recent work has considered the realistic case where the
trajectories are uncertain; however, only simple uncertainty models have been
proposed, which do not allow for accurate probabilistic search. In this paper,
we fill this gap by addressing probabilistic nearest neighbor queries in
databases with uncertain trajectories modeled by stochastic processes,
specifically the Markov chain model. We study three nearest neighbor query
semantics that take as input a query state or trajectory $q$ and a time
interval. For some queries, we show that no polynomial time solution can be
found. For problems that can be solved in PTIME, we present exact query
evaluation algorithms, while for the general case, we propose a sophisticated
sampling approach, which uses Bayesian inference to guarantee that sampled
trajectories conform to the observation data stored in the database. This
sampling approach can be used in Monte-Carlo based approximation solutions. We
include an extensive experimental study to support our theoretical results.


title: On the extensions of Di Nola's Theorem

abstract:
  The main aim of this paper is to present a direct proof of Di Nola's
representation Theorem for MV-algebras and to extend his results to the
restriction of the standard MV-algebra on rational numbers. The results are
based on a direct proof of the theorem which says that any finite partial
subalgebra of a linearly ordered MV-algebra can be embedded into $\mathbb Q\cap
[0,1].$


title:
Calibration diagnostics for point process models via the probability
  integral transform

abstract:
  We propose the use of the probability integral transform (PIT) for model
validation in point process models. The simple PIT diagnostics assess the
calibration of the model and can detect inconsistencies in both the intensity
and the interaction structure. For the Poisson model, the PIT diagnostics can
be calculated explicitly. Generally, the calibration may be assessed
empirically based on random draws from the model and the method applies to
processes of any dimension.


title: Composite tunnel number one genus two handlebody-knots

abstract: We characterize composite tunnel number one genus two handlebody-knots.


title: Embeddings of maximal tori in orthogonal groups

abstract:
  We give necessary and sufficient conditions for an orthogonal group defined
over a field of characteristic not 2 to contain a maximal torus of a given
type.


title: Recurrence time in the quantum dynamics of the 1D Bose gas

abstract:
  Recurrence time is evaluated for some initial quantum states in the
one-dimensional Bose gas with repulsive short-range interactions. In the
relatively strong and weak coupling cases some different types of initial
states show almost complete recurrence and the estimates of recurrence time are
proportional to some powers of the system size at least in some range of the
system size. They are much longer than in the case of free particles such as
100 times. In the free-bosonic and free-fermionic regimes we evaluate the
recurrence time rigorously, which is proportional to the square of the system
size. The estimate of recurrence time is given by the order of ten milliseconds
in the corresponding experimental systems of cold atoms trapped in one
dimension of ten micrometers in length. It is much shorter than the estimate in
a generic quantum many-body system, which may be as long as the age of the
universe.


title:
A Semi-Analytical Description for the Formation and Gravitational
  Evolution of Protoplanetary Disks

abstract:
  We investigate the formation process of self-gravitating protoplanetary disks
in unmagnetized molecular clouds. The angular momentum is redistributed by the
action of gravitational torques in the massive disk during its early formation.
We develop a simplified one-dimensional accretion disk model that takes into
account the infall of gas from the envelope onto the disk and the transfer of
angular momentum in the disk with an effective viscosity. First we evaluate the
gas accretion rate from the cloud core onto the disk by approximately
estimating the effects of gas pressure and gravity acting on the cloud core. We
formulate the effective viscosity as a function of the Toomre Q parameter that
measures the local gravitational stability of the rotating thin disk. We use a
function for viscosity that changes sensitively with Q when the disk is
gravitationally unstable. We find a strong self-regulation mechanism in the
disk evolution. During the formation stage of protoplanetary disks, the
evolution of the surface density does not depend on the other details of the
modeling of effective viscosity, such as the prefactor of the viscosity
coefficient. Next, to verify our model, we compare the time evolution of the
disk calculated with our formulation with that of three-dimensional
hydrodynamical simulations. The structures of the resultant disks from the
one-dimensional accretion disk model agree well with those of the
three-dimensional simulations. Our model is a useful tool for the further
modeling of chemistry, radiative transfer, and planet formation in
protoplanetary disks.


title:
More on the skew-spectra of bipartite graphs and Cartesian products of
  graphs

abstract:
  Given a graph $G$, let $G^\sigma$ be an oriented graph of $G$ with the
orientation $\sigma$ and skew-adjacency matrix $S(G^\sigma)$. Then the spectrum
of $S(G^\sigma)$ is called the skew-spectrum of $G^\sigma$, denoted by
$Sp_S(G^\sigma)$. It is known that a graph $G$ is bipartite if and only if
there is an orientation $\sigma$ of $G$ such that $Sp_S(G^\sigma)=iSp(G)$. In
[D. Cui, Y. Hou, On the skew spectra of Cartesian products of graphs, Electron.
J. Combin. 20(2013), #P19], Cui and Hou conjectured that such orientation of a
bipartite graph is unique under switching-equivalence. In this paper, we prove
that the conjecture is true. Moreover, we give an orientation of the Cartesian
product of a bipartite graph and a graph, and then determine the skew-spectrum
of the resulting oriented product graph, which generalizes Cui and Hou's
result, and can be used to construct more oriented graphs with maximum skew
energy.


title:
Young Open Star Clusters: The Spatial Distribution of Metallicity in the
  Solar Neighborhood

abstract:
  We perform a comparative analysis of the spatial distribution of young (<50
Myr) open star clusters and field Cepheids with different metallicities. A
significant fraction of young clusters are shown to have low metallicities
atypical of field Cepheids. Both types of objects exhibit approximately equal
(in magnitude) negative radial metallicity gradients, while their azimuthal
metallicity gradients differ outside the error limits and have opposite signs.
Among the stellar complexes identified by young clusters, the most metal-poor
clusters are grouped in the Perseus complex. It is the clusters of this complex
that are responsible for the radial and azimuthal metallicity gradients among
young clusters. The described properties are indicative of a weak mixing of
interstellar matter before the onset of star formation there. Significant
differences between the spatial distributions of open clusters and field stars
with different metallicities suggest different conditions required for the
formation of these types of objects.


title: MRI-driven angular momentum transport in protoplanetary disks

abstract:
  Angular momentum transport in accretion disk has been the focus of intense
research in theoretical astrophysics for many decades. In the past twenty
years, MHD turbulence driven by the magnetorotational instability has emerged
as an efficient mechanism to achieve that goal. Yet, many questions and
uncertainties remain, among which the saturation level of the turbulence. The
consequences of the magnetorotational instability for planet formation models
are still being investigated. This lecture, given in September 2012 at the
school "Role and mechanisms of angular momentum transport in the formation and
early evolution of stars" in Aussois (France), aims at introducing the
historical developments, current status and outstanding questions related to
the magnetorotational instability that are currently at the forefront of
academic research.