title:
Large scale separation and resonances within LHC range from a prototype
  BSM model

abstract:
  Many theories describing physics beyond the Standard Model rely on a large
separation of scales. Large scale separation arises in models with mass-split
flavors if the system is conformal in the ultraviolet but chirally broken in
the infrared. Because of the conformal fixed point, these systems exhibit
hyperscaling and a highly constrained resonance spectrum. We derive
hyperscaling relations and investigate the realization of one such system with
four light and eight heavy flavors. Our numerical simulations confirm that both
light-light and heavy-heavy resonance masses show hyperscaling and depend only
on the ratio of the light and heavy flavor masses. The heavy-heavy spectrum is
qualitatively different from QCD and exhibits quarkonia with masses not
proportional to the constituent quark mass. These resonances are only a few
times heavier than the light-light ones, which would put them within reach of
the LHC.


title: Regularity of Powers of Bipartite Graphs

abstract:
  Let $G$ be a finite simple graph and $I(G)$ denote the corresponding edge
ideal. For all $s \geq 1$, we obtain upper bounds for reg$(I(G)^s)$ for
bipartite graphs. We then compare the properties of $G$ and $G'$, where $G'$ is
the graph associated with the polarization of the ideal $(I(G)^{s+1} :
e_1\cdots e_s)$, where $e_1,\ldots e_s$ are edges of $G$. Using these results,
we explicitly compute reg$(I(G)^s)$ for several subclasses of bipartite graphs.


title: On triviality of reduced Whitehead group over Henselian fields

abstract:
  Let $F$ be a Henselian field of $q$-cohomological dimension $3$, where $q$ is
a prime. Let $\Gamma_F$ be the totally ordered abelian value group of $F$ and
let $D$ be a central division algebra over $F$ of index a power of $q$ such
that the characteristic of the residue field, $\overline{F}$ is coprime to $q$.
We show that when $1\leq\dim_{\mathbb{F}_q}(\Gamma_F/q\Gamma_F)\leq 3$, the
reduced Whitehead group of $D$ is trivial.


title: Positive Scalar Curvature and Poincare Duality for Proper Actions

abstract:
  For G an almost-connected Lie group, we study G-equivariant index theory for
proper co-compact actions with various applications, including obstructions to
and existence of G-invariant Riemannian metrics of positive scalar curvature.
We prove a rigidity result for almost-complex manifolds, generalising Hattori's
results, and an analogue of Petrie's conjecture. When G is an almost-connected
Lie group or a discrete group, we establish Poincare duality between
G-equivariant K-homology and K-theory, observing that Poincare duality does not
necessarily hold for general G.


title:
Uniform Approximation of Solutions by Elimination of Intermediate
  Species in Deterministic Reaction Networks

abstract:
  Chemical reactions often proceed through the formation and the consumption of
intermediate species. An example is the creation and subsequent degradation of
the substrate-enzyme complexes in an enzymatic reaction. In this paper we
provide a setting, based on ordinary differential equations, in which the
presence of intermediate species has little effect on the overall dynamics of a
biological system. The result provides a method to perform model reduction by
elimination of intermediate species. We study the problem in a multiscale
setting, where the species abundances as well a the reaction rates scale to
different orders of magnitudes. The different time and concentration scales are
parameterised by a single parameter $N$. We show that a solution to the
original reaction system is uniformly approximated on compact time intervals to
a solution of a reduced reaction system without intermediates and to a solution
of a certain limiting reaction systems, which does not depend on $N$. Known
approximation techniques such as the theorems by Tikhonov and Fenichel cannot
readily be used in this framework.


title: Remarks on the Graovac-Ghorbani index of bipartite graphs

abstract:
  The atom-bond connectivity (ABC) index is a well-known degree-based molecular
structure descriptor with a variety of chemical applications. In 2010 Graovac
and Ghorbani introduced a distance-based analog of this index, the
Graovac-Ghorbani (GG) index, which yielded promising results when compared to
analogous descriptors. In this paper, we investigate the structure of graphs
that maximize and minimize the GG index. Specifically, we show that amongst all
bipartite graphs, the minimum GG index is attained by a complete bipartite
graph, while the maximum GG index is attained by a path or a cycle-like graph;
the structure of the resulting graph depends on the number of vertices. Through
the course of the research, we also derive an asymptotic estimate of the GG
index of paths. In order to obtain our results, we introduce a normalized
version of the GG index and call it the normalized Graovac-Ghorbani (NGG)
index. Finally, we discuss some related open questions as a potential extension
of our work.


title:
3$\alpha$-cluster structure and monopole transition in $^{12}$C and
  $^{14}$C

abstract:
  3$\alpha$-cluster structures and monopole transitions of $0^+$ states in
$^{12}$C and $^{14}$C were investigated with $3\alpha$- and
$^{10}$Be+$\alpha$-cluster models. A gas-like $3\alpha$ state and a
bending-chain $3\alpha$ state were obtained in the $0^+_2$ and $0^+_3$ states
of $^{12}$C, respectively. In $^{14}$C, a linear-chain 3$\alpha$ structure is
found in the $0^+_4$ state near the $^{10}$Be+$\alpha$ threshold, but a cluster
gas-like state does not appear because valence neutrons attract $\alpha$
clusters and suppress spatial development of 3$\alpha$ clustering. It was found
that the linear-chain state in $^{14}$C is stabilized against the bending and
$\alpha$ escaping modes by valence neutrons. The monopole transition strengths
in $^{12}$C are enhanced by $3\alpha$-cluster developing, whereas, those in
$^{14}$C are not enhanced so much because of the tight binding of $\alpha$
clusters by valence neutrons.


title: Consensus of Dependent Opinions

abstract:
  Providing opinions through labeling of images, tweets, etc. have drawn
immense interest in crowdsourcing markets. This invokes a major challenge of
aggregating multiple opinions received from different crowd workers for
deriving the final judgment. Generally, opinion aggregation models deal with
independent opinions, which are given unanimously and are not visible to all.
However, in many real-life cases, it is required to make the opinions public as
soon as they are received. This makes the opinions dependent and might
incorporate some bias. In this paper, we address a novel problem, hereafter
denoted as dependent judgment analysis, and discuss the requirements for
developing an appropriate model to deal with this problem. The challenge
remains to be improving the consensus by revealing true opinions.


title: Android Assistant EyeMate for Blind and Blind Tracker

abstract:
  At present many blind assistive systems have been implemented but there is no
such kind of good system to navigate a blind person and also to track the
movement of a blind person and rescue him/her if he/she is lost. In this paper,
we have presented a blind assistive and tracking embedded system. In this
system the blind person is navigated through a spectacle interfaced with an
android application. The blind person is guided through Bengali/English voice
commands generated by the application according to the obstacle position. Using
voice command a blind person can establish voice call to a predefined number
without touching the phone just by pressing the headset button. The blind
assistive application gets the latitude and longitude using GPS and then sends
them to a server. The movement of the blind person is tracked through another
android application that points out the current position in Google map. We took
distances from several surfaces like concrete and tiles floor in our experiment
where the error rate is 5%.


title: Securely Outsourcing Large Scale Eigen Value Problem to Public Cloud

abstract:
  Cloud computing enables clients with limited computational power to
economically outsource their large scale computations to a public cloud with
huge computational power. Cloud has the massive storage, computational power
and software which can be used by clients for reducing their computational
overhead and storage limitation. But in case of outsourcing, privacy of
client's confidential data must be maintained. We have designed a protocol for
outsourcing large scale Eigen value problem to a malicious cloud which provides
input/output data security, result verifiability and client's efficiency. As
the direct computation method to find all eigenvectors is computationally
expensive for large dimensionality, we have used power iterative method for
finding the largest Eigen value and the corresponding Eigen vector of a matrix.
For protecting the privacy, some transformations are applied to the input
matrix to get encrypted matrix which is sent to the cloud and then decrypting
the result that is returned from the cloud for getting the correct solution of
Eigen value problem. We have also proposed result verification mechanism for
detecting robust cheating and provided theoretical analysis and experimental
result that describes high-efficiency, correctness, security and robust
cheating resistance of the proposed protocol.


title: Bounds and Conjectures for additive divisor sums

abstract:
  Additive divisor sums play a prominent role in the theory of the moments of
the Riemann zeta function. There is a long history of determining sharp
asymptotic formula for the shifted convolution sum of the ordinary divisor
function. In recent years, it has emerged that a sharp asymptotic formula for
the shifted convolution sum of the triple divisor function would be useful in
evaluating the sixth moment of the Riemann zeta function. In this article, we
study $D_{k,\ell}(x) = \sum_{n \le x} \tau_k(n) \tau_{\ell}(n+h)$ where
$\tau_k$ and $\tau_{\ell}$ are the $k$-th and $\ell$-th divisor functions. The
main result is a lower bound of the correct order of magnitude for
$D_{k,\ell}(x,h)$, uniform in $h$. In addition, the conjectural asymptotic
formula for $D_{k,\ell}(x,h)$ is studied. Using an argument of Ivi\'{c} and
Conrey-Gonek the leading term in the conjectural asymptotic formula is
simplified. In addition, a probabilistic method is presented which gives the
same leading term. Finally, we show that these two methods give the same answer
as in a recent probabilistic argument of Terry Tao.


title:
Scaling Theory of a Compressibility-Driven Metal-Insulator Transition in
  a Two-Dimensional Electron Fluid

abstract:
  We present a scaling description of a metal-insulator transition in
two-dimensional electron systems that is driven by a vanishing compressibility
rather than a vanishing diffusion coefficient. A small set of basic assumptions
leads to a consistent theoretical framework that is compatible with existing
transport and compressibility measurements, and allows to make predictions for
other observables. We also discuss connections between these ideas and other
theories of transitions to an incompressible quantum fluid.


title:
6d Dirac fermion on a rectangle; scrutinizing boundary conditions, mode
  functions and spectrum

abstract:
  We classify possible boundary conditions of a 6d Dirac fermion $\Psi$ on a
rectangle under the requirement that the 4d Lorentz structure is maintained,
and derive the profiles and spectrum of the zero modes and nonzero KK modes
under the two specific boundary conditions, (i) 4d-chirality positive
components being zero at the boundaries and (ii) 2d-chirality positive
components being zero at the boundaries. In the case of (i), twofold
degenerated chiral zero modes appear which are localized towards specific
directions of the rectangle pointed by an angle parameter $\theta$. This leads
to an implication for a new direction of pursuing the origin of three
generations in the matter fields of the standard model, even though
triple-degenerated zero modes are not realized in the six dimensions. The
emergence of the angle parameter $\theta$ originates from a rotational symmetry
in the degenerated chiral zero modes on the rectangle extra dimensions since
they do not feel the boundaries. In the case of (ii), this rotational symmetry
is promoted to the two-dimensional conformal symmetry though no chiral massless
zero mode appears. We also discuss the correspondence between our model on a
rectangle and orbifold models in some details.


title: Features Fusion for Classification of Logos

abstract:
  In this paper, a logo classification system based on the appearance of logo
images is proposed. The proposed classification system makes use of global
characteristics of logo images for classification. Color, texture, and shape of
a logo wholly describe the global characteristics of logo images. The various
combinations of these characteristics are used for classification. The
combination contains only with single feature or with fusion of two features or
fusion of all three features considered at a time respectively. Further, the
system categorizes the logo image into: a logo image with fully text or with
fully symbols or containing both symbols and texts.. The K-Nearest Neighbour
(K-NN) classifier is used for classification. Due to the lack of color logo
image dataset in the literature, the same is created consisting 5044 color logo
images. Finally, the performance of the classification system is evaluated
through accuracy, precision, recall and F-measure computed from the confusion
matrix. The experimental results show that the most promising results are
obtained for fusion of features.


title: A Framework for Scientific Paper Retrieval and Recommender Systems

abstract:
  Information retrieval (IR) and recommender systems (RS) have been employed
for addressing search tasks executed during literature review and the overall
scholarly communication lifecycle. Majority of the studies have concentrated on
algorithm design for improving the accuracy and usefulness of these systems.
Contextual elements related to the scholarly tasks have been largely ignored.
In this paper, we propose a framework called the Scientific Paper Recommender
and Retrieval Framework (SPRRF) that combines aspects of user role modeling and
user-interface features with IR/RS components. The framework is based on eight
emergent themes identified from participants feedback in a user evaluation
study conducted with a prototype assistive system. 119 researchers participated
in the study for evaluating the prototype system that provides recommendations
for two literature review and one manuscript writing tasks. This holistic
framework is meant to guide future studies in this area.


title: Baryon Number Fluctuations in Quasi-particle Model

abstract:
  Baryon number fluctuations are sensitive to the QCD phase transition and QCD
critical point. According to the Feynman rules of finite-temperature field
theory, we calculated various order moments and cumulants of the baryon number
distributions in the quasi-particle model of quark gluon plasma. Furthermore,
we compared our results with the experimental data measured by the STAR
experiment at RHIC. It is found that the experimental data can be well
described by the model for the colliding energies above 30 GeV and show large
discrepancies at low energies. It can put new constraint on qQGP model and also
provide a baseline for the QCD critical point search in heavy-ion collisions at
low energies.


title: Exploring Nf=2+1 QCD thermodynamics from the gradient flow

abstract:
  The energy-momentum tensor plays an important role in QCD thermodynamics. Its
expectation value contains information of the pressure and the energy density
as its diagonal part. Further properties like viscosity and specific heat can
be extracted from its correlation function. Recently a new method based on the
gradient flow was introduced to calculate the energy-momentum tensor on the
lattice, and has been successfully applied to quenched QCD.
  In this paper, we apply the gradient flow method to calculate the
energy-momentum tensor in (2+1)-flavor QCD. As the first application of the
method with dynamical quarks, we study at a single but fine lattice spacing
a=0.07 fm with heavy u and d quarks ($m_\pi/m_\rho=0.63$) and approximately
physical s quark. Performing simulations on lattices with Nt=16 to 4, the
temperature range of T=174-697 MeV is covered. We find that the results of the
pressure and the energy density by the gradient flow method are consistent with
the previous results using the T-integration method at T<280 MeV, while the
results show disagreement at T>350 MeV (Nt<8), presumably due to the small-Nt
lattice artifact of $O((aT)^2)=O(1/N_t^2)$.
  We also apply the gradient flow method to evaluate the chiral condensate
taking advantage of the gradient flow method that renormalized quantities can
be directly computed avoiding the difficulty of explicit chiral violation with
lattice quarks. We compute the renormalized chiral condensate in the MS-bar
scheme at renormalization scale $\mu=2$ GeV with a high precision to study the
temperature dependence of the chiral condensate and its disconnected
susceptibility. Even with the Wilson-type quark action, we obtain the chiral
condensate and its disconnected susceptibility showing a clear signal of
pseudocritical temperature at T~190 MeV related to the chiral restoration
crossover.


title: Landau-Zener-Stueckelberg physics with a singular continuum of states

abstract:
  This work addresses the dynamical quantum problem of a driven discrete energy
level coupled to a semi-infinite continuum whose density of states has a
square-root-type singularity, such as states of a free particle in one
dimension or quasiparticle states in a BCS superconductor. The system dynamics
is strongly affected by the quantum-mechanical repulsion between the discrete
level and the singularity, which gives rise to a bound state, suppresses the
decay into the continuum, and can produce Stueckelberg oscillations. This
quantum coherence effect may limit the performance of mesoscopic
superconducting devices, such as quantum electron turnstile.


title:
On the nature of FRB 150418: clues from European VLBI Network and
  e-MERLIN observations

abstract:
  We investigate the nature of the compact, and possibly variable nuclear radio
source in the centre of WISE J0716-19, the proposed host galaxy of fast radio
burst, FRB 150418. We observed WISE J0716-19 at 5.0 GHz with the European VLBI
Network four times between 2016 March 16 and June 2. At three epochs, we
simultaneously observed the source with e-MERLIN at the same frequency. We
detected a compact source in the EVN data in each epoch with a significance up
to ~8sigma. The four epochs yielded consistent results within their
uncertainties, for both peak surface intensity and positions. The mean values
for these quantities are I_peak = (115+-9) {\mu}Jy/beam and r.a. =
07:16:34.55496(7), dec. = -19:00:39.4754(8), respectively. The e-MERLIN data
provided ~3-5sigma detections, at a position consistent with those of the EVN
data. The presence of emission on angular scales intermediate between the EVN
and e-MERLIN is consistent with being null. The brightness temperature of the
EVN core is Tb~10^8.5K, close to the value required by Akiyama & Johnson (2016)
to explain the radio properties of WISE J0716-19 in terms of interstellar
induced short-term variability. Our observations provide direct, independent
evidence of the existence of a nuclear compact source in WISE J0716-19, a
physical scenario with no evident connection with FRB 150418. However, the EVN
data do not show indication of the variability observed with the VLA.


title:
Determination of Coronal Mass Ejection physical parameters from
  combination of polarized visible light and UV Lyman-$\alpha$ observations

abstract:
  Visible-light observations of Coronal Mass Ejections (CMEs) performed with
coronagraphs and heliospheric imagers (in primis on board the SOHO and STEREO
missions) have offered so far the best way to study the kinematics and
geometrical structure of these fundamental events. Nevertheless, it has been
widely demonstrated that only combination of multi-wavelength data (including
X-ray spectra, EUV images, EUV-UV spectra, and radio dynamic spectra) can
provide complete information on the plasma temperature and density
distributions, non-thermal motions, magnetic fields, and other physical
parameters, for both CMEs and CME-related phenomena. In this work, we analyze
three CMEs by combining simultaneous data acquired in the polarized visible
light by the LASCO-C2 coronagraph and in the UV H I Lyman-$\alpha$ line (1216
\AA) by the UVCS spectrometer, in order to estimate the CME plasma electron
density (using the polarization-ratio technique to infer the 3D structure of
the CME) and temperature (from the comparison between the expected and measured
Lyman-$\alpha$ intensities) along the UVCS field of view. This analysis is
primarily aimed at testing the diagnostic methods that will be applied to
coronagraphic observations of CMEs delivered by the Metis instrument on board
the next ESA-Solar Orbiter mission. We find that CME cores are usually
associated with cooler plasma ($T \sim 10^6$ K), and that a significant
increase of the electron temperatures is observed from the core to the front of
the CME (where $T > 10^{6.3}$ K), which seems to be correlated, in all cases,
with the morphological structure of the CME as derived from visible-light
images.


title: Struggles with the Continuum

abstract:
  Our assumption that spacetime is a continuum leads to many challenges in
mathematical physics. Singularities, divergent integrals and the like threaten
many of our favorite theories, from Newtonian gravity to classical
electrodynamics, quantum electrodynamics and the Standard Model. In general
relativity, singularities are intimately connected to some of the theory's most
dramatic successful predictions. We survey these problems and the large amount
of work that has gone into dealing with them.

categories: math-ph gr-qc hep-th math.MP physics.hist-ph


title:
Discovery of a Perseus-like cloud in the early Universe: HI-to-H2
  transition, carbon monoxide and small dust grains at zabs=2.53 towards the
  quasar J0000+0048

abstract:
  We present the discovery of a molecular cloud at zabs=2.5255 along the line
of sight to the quasar J0000+0048. We perform a detailed analysis of the
absorption lines from ionic, neutral atomic and molecular species in different
excitation levels, as well as the broad-band dust extinction. We find that the
absorber classifies as a Damped Lyman-alpha system (DLA) with
logN(HI)(cm^-2)=20.8+/-0.1. The DLA has super-Solar metallicity with a
depletion pattern typical of cold gas and an overall molecular fraction ~50%.
This is the highest f-value observed to date in a high-z intervening system.
Most of the molecular hydrogen arises from a clearly identified narrow (b~0.7
km/s), cold component in which CO molecules are also found, with logN(CO)~15.
We study the chemical and physical conditions in the cold gas. We find that the
line of sight probes the gas deep after the HI-to-H2 transition in a ~4-5
pc-size cloud with volumic density nH~80 cm^-3 and temperature of only 50 K.
Our model suggests that the presence of small dust grains (down to about 0.001
{\mu}m) and high cosmic ray ionisation rate (zeta_H a few times 10^-15 s^-1)
are needed to explain the observed atomic and molecular abundances. The
presence of small grains is also in agreement with the observed steep
extinction curve that also features a 2175 A bump. The properties of this cloud
are very similar to what is seen in diffuse molecular regions of the nearby
Perseus complex. The high excitation temperature of CO rotational levels
towards J0000+0048 betrays however the higher temperature of the cosmic
microwave background. Using the derived physical conditions, we correct for a
small contribution (0.3 K) of collisional excitation and obtain TCMB(z =
2.53)~9.6 K, in perfect agreement with the predicted adiabatic cooling of the
Universe. [abridged]


title:
Structured Sparse Principal Components Analysis with the TV-Elastic Net
  penalty

abstract:
  Principal component analysis (PCA) is an exploratory tool widely used in data
analysis to uncover dominant patterns of variability within a population.
Despite its ability to represent a data set in a low-dimensional space, the
interpretability of PCA remains limited. However, in neuroimaging, it is
essential to uncover clinically interpretable phenotypic markers that would
account for the main variability in the brain images of a population. Recently,
some alternatives to the standard PCA approach, such as Sparse PCA, have been
proposed, their aim being to limit the density of the components. Nonetheless,
sparsity alone does not entirely solve the interpretability problem, since it
may yield scattered and unstable components. We hypothesized that the
incorporation of prior information regarding the structure of the data may lead
to improved relevance and interpretability of brain patterns. We therefore
present a simple extension of the popular PCA framework that adds structured
sparsity penalties on the loading vectors in order to identify the few stable
regions in the brain images accounting for most of the variability. Such
structured sparsity can be obtained by combining l1 and total variation (TV)
penalties, where the TV regularization encodes higher order information about
the structure of the data. This paper presents the structured sparse PCA
(denoted SPCA-TV) optimization framework and its resolution. We demonstrate the
efficiency and versatility of SPCA-TV on three different data sets. The gains
of SPCA-TV over unstructured approaches are significant,since SPCA-TV reveals
the variability within a data set in the form of intelligible brain patterns
that are easy to interpret, and are more stable across different samples.


title:
Microscopic phase-space exploration modeling of $^{258}$Fm spontaneous
  fission

abstract:
  We show that the total kinetic energy (TKE) of nuclei after the spontaneous
fission of $^{258}$Fm can be well reproduced using simple assumptions on the
quantum collective phase-space explored by the nucleus after passing the
fission barrier. Assuming energy conservation and phase-space exploration
according to the stochastic mean-field approach, a set of initial densities is
generated. Each density is then evolved in time using the nuclear
time-dependent density-functional theory. This approach goes beyond mean-field
by allowing spontaneous symmetry breaking as well as a wider dynamical
phase-space exploration leading to larger fluctuations in collective space. The
total kinetic energy and mass distributions are calculated. New information on
the fission process: fluctuations in scission time, strong correlation between
TKE and collective deformation of daughter nuclei as well as pre- and
post-scission particle emission, are obtained.


title: Vertex weighted Laplacian graph energy and other topological indices

abstract:
  Let $G$ be a graph with a vertex weight $\omega$ and the vertices
$v_1,\ldots,v_n$. The Laplacian matrix of $G$ with respect to $\omega$ is
defined as
  $L_\omega(G)=\mathrm{diag}(\omega(v_1),\cdots,\omega(v_n))-A(G)$, where
$A(G)$ is the adjacency matrix of $G$. Let $\mu_1,\cdots,\mu_n$ be eigenvalues
of $L_\omega(G)$. Then the Laplacian energy of $G$ with respect to $\omega$
defined as $LE_\omega (G)=\sum_{i=1}^n\big|\mu_i - \bar{\omega}\big|$, where
$\bar{\omega}$ is the average of $\omega$, i.e.,
$\bar{\omega}=\dfrac{\sum_{i=1}^{n}\omega(v_i)}{n}$. In this paper we consider
several natural vertex weights of $G$ and obtain some inequalities between the
ordinary and Laplacian energies of $G$ with corresponding vertex weights.
Finally, we apply our results to the molecular graph of toroidal fullerenes (or
achiral polyhex nanotorus).


title:
The 1-loop vacuum polarization for a graphene-like medium in an external
  magnetic field; corrections to the Coulomb potential

abstract:
  I calculate the 1-loop vacuum polarization $\Pi_{\mu\nu}(k,B,a)$ for a photon
of momentum $k=(\hat k,k_3)$ interacting with the electrons of a thin medium of
thickness $2a$ simulating graphene, in the presence of a constant and uniform
external magnetic field $B$ orthogonal to it (parallel to $k_3$). Calculations
are done with the techniques of Schwinger, adapted to the geometry and
Hamiltonian under scrutiny. The situation gets more involved than for the
electron self-energy because the photon is now allowed to also propagate
outside the medium. This makes $\Pi_{\mu\nu}$ factorize into a quantum,
"reduced" $T_{\mu\nu}(\hat k,B)$ and a transmittance function $V(k,a)$, in
which the geometry of the sample and the resulting confinement of the
$\gamma\,e^+\,e^-$ vertices play major roles. This drags the results away from
reduced QED$_{3+1}$ on a 2-brane. The finiteness of $V$ at $k^2=0$ is an
essential ingredient to fulfill suitable renormalization condition for
$\Pi_{\mu\nu}$ and to fix the corresponding counterterms. Their connection with
the transversality of $\Pi_{\mu\nu}$ is investigated. The corrections to the
Coulomb potential and their dependence on $B$ strongly differ from QED$_{3+1}$.


title:
Zariski-van Kampen theorems for singular varieties --- an approach via
  the relative monodromy variation

abstract:
  The classical Zariski-van Kampen theorem gives a presentation of the
fundamental group of the complement of a complex algebraic curve in
$\mathbb{P}^2$. The first generalization of this theorem to singular
(quasi-projective) varieties was given by the first author. In both cases, the
relations are generated by the standard monodromy variation operators
associated with the special members of a generic pencil of hyperplane sections.
In the present paper, we give a new generalization in which the relations are
generated by the relative monodromy variation operators introduced by D.
Ch\'eniot and the first author. The advantage of using the relative operators
is not only to cover a larger class of varieties but also to unify the
Zariski-van Kampen type theorems for the fundamental group and for higher
homotopy groups. In the special case of non-singular varieties, the main result
of this paper was conjectured by D. Ch\'eniot and the first author.


title:
Some dependence results between the spreading speed and the coefficients
  of the space--time periodic Fisher--KPP equation

abstract:
  We investigate in this paper the dependence relation between the space-time
periodic coefficients $A, q$ and $\mu$ of the reaction-diffusion equation
$\partial_t u - \nabla \cdot (A(t, x)\nabla u) + q(t, x) \cdot \nabla u =
\mu(t, x) u(1 - u)$, and the spreading speed of the solutions of the Cauchy
problem associated with this equation and compactly supported initial data. We
prove in particular that (1) taking the spatial or temporal average of $\mu$
decreases the minimal speed, (2) if the coefficients do not depend on $t$ and
$q\not\equiv 0$, then increasing the amplitude of the diffusion matrix $A$
increases the minimal speed, (3) if $A = I_N$, $\mu$ is a constant, then the
introduction of a space periodic drift term $q = \nabla Q$ increases the
minimal speed. To prove these results, we use a variational characterization of
the spreading speed that involves a family of periodic principal eigenvalues
associated with the linearization of the equation near 0. We are thus back to
the investigation of the dependence relation between this family of eigenvalues
and the coefficients.


title: Some mixed character sum identities of Katz II

abstract:
  A conjecture connected with quantum physics led N. Katz to discover some
amazing mixed character sum identities over a field of q elements, where q is a
power of a prime p > 3. His proof required deep algebro-geometric techniques,
and he expressed interest in finding a more straightforward direct proof. The
first author recently gave such a proof of his identities when q = 1 (mod 4),
and this paper provides such a proof for the remaining case q = 3 (mod 4). Our
proofs are valid for all characteristics p > 2. Along the way we prove some
elegant new character sum identities.


title:
Potential landscape and flux field theory for turbulence and
  nonequilibrium fluid systems

abstract:
  Turbulence is a paradigm for far-from-equilibrium systems without time
reversal symmetry. To capture the nonequilibrium irreversible nature of
turbulence and investigate its implications, we develop a potential landscape
and flux field theory for turbulent flow and more general nonequilibrium fluid
systems governed by stochastic Navier-Stokes equations. We find that
equilibrium fluid systems with time reversibility are characterized by a
detailed balance constraint that quantifies the detailed balance condition. In
nonequilibrium fluid systems with nonequilibrium steady states, detailed
balance breaking leads directly to a pair of interconnected consequences,
namely, the non-Gaussian potential landscape and the irreversible probability
flux, forming a 'nonequilibrium trinity'. The nonequilibrium trinity
characterizes the nonequilibrium irreversible essence of fluid systems with
intrinsic time irreversibility and is manifested in various aspects of these
systems. The nonequilibrium stochastic dynamics of fluid systems including
turbulence with detailed balance breaking is shown to be driven by both the
non-Gaussian potential landscape gradient and the irreversible probability
flux, together with the reversible convective force and the stochastic stirring
force. We reveal an underlying connection of the energy flux essential for
turbulence energy cascade to the irreversible probability flux and the
non-Gaussian potential landscape generated by detailed balance breaking. Using
the energy flux as a center of connection, we demonstrate that the four-fifths
law in fully developed turbulence is a consequence and reflection of the
nonequilibrium trinity. We also show how the nonequilibrium trinity can affect
the scaling laws in turbulence.


title: Traveling fronts in space-time periodic media

abstract:
  This paper is concerned with the existence of pulsating traveling fronts for
the equation: $\partial_t u - \nabla \cdot (A(t, x)\nabla u) + q(t, x) \cdot
\nabla u = f (t, x, u)$, (1) where the diffusion matrix $A$, the advection term
$q$ and the reaction term $f$ are periodic in $t$ and $x$. We prove that there
exist some speeds $c^*$ and $c^{**}$ such that there exists a pulsating
traveling front of speed $c$ for all $c\ge c^{**}$ and that there exists no
such front of speed $c<c^*$. We also give some spreading properties for
front-like initial data. In the case of a KPP-type reaction term, we prove that
$c^* = c^{**}$ and we characterize this speed with the help of a family of
eigenvalues associated with the equation. If $f$ is concave with respect to
$u$, we prove some Lipschitz continuity for the profile of the pulsating
traveling front.
  Cet articl{\'e} etudie l'existence de fronts pulsatoires pour l'\'equation :
$\partial_t u - \nabla \cdot (A(t, x)\nabla u) + q(t, x) \cdot \nabla u = f (t,
x, u)$, (2) o\`u la matrice de diffusion A, le terme d'advection $q$ et le
terme de r{\'e}action $f$ sont p{\'e}riodiques en $t$ et en $x$. Nous prouvons
l'existence de deux vitesses $c^*$ et $c^{**}$ telles qu'il existe un front
pulsatoire de vitesse $c$ pour tout $c \ge c^{**}$ et qu'il n'existe pas de tel
front de vitesse $c<c^*$. Nous donnons egalement des propri{\'e}t{\'e}s de
spreading pour des donn{\'e}es initiales ressemblant a des fronts. Dans le cas
d'un terme de r{\'e}action de type KPP, nous prouvons que $c^* = c^{**}$ et
nous caract{\'e}risons cette vitess{\`e} a l'aide d'une famille de valeurs
propres associ{\'e}{\`e} a l'\'equation. Si $f$ est concave en $u$, nous
montrons que le profil du front pulsatoire construit est lipschitzien.


title:
Observation of two distinct pairs fluctuation lifetimes and
  supercurrents in the pseudogap regime of cuprate junctions

abstract:
  Pairs fluctuation supercurrents and inverse lifetimes were measured on
epitaxial c-axis junctions of the cuprates in the pseudogap regime, with a
$PrBa_2Cu_3O_{7-\delta}$ barrier sandwiched in between two
$YBa_2Cu_3O_{7-\delta}$ or doped $YBa_2Cu_3O_y$ electrodes, with or without
magnetic fields parallel to the a-b planes. All junctions had a $\rm
T_c(high)\approx 85-90$ K and a $\rm T_c(low)\approx 50-55$ K electrodes,
allowing us to study pairs fluctuation supercurrents and inverse life times in
between these two temperatures. In junctions with a pseudogap electrode under
zero field, an excesss current due to pair fluctuations was observed which
persisted at temperatures above $\rm T_c(low)$, in the pseudogap regime, and up
to about $\rm T_c(high)$. No such excess current was observed in junctions
without a pseudo-gap in the electrode. The measured conductance spectra at
temperatures above $\rm T_c(low)$ were fitted using a modified fluctuations
model by Scalapino [Phys. Rev. Lett. \textbf{24}, 1052(1970)] of a junction
with a serial resistance. We found that in the pseudo-gap regime, the
conductance vs voltage consists of a narrow peak sitting on top of a very broad
peak. This yielded two distinct pairs fluctuation lifetimes in the pseudogap
electrode which differ by an order of magnitude up to about $\rm T_c(high)$.
Under in-plane fields, these two lifetime values remain separated in two
distinct groups, which varied with increasing field moderately. We also found
that detection of Amperian pairing [Phys. Rev. X \textbf{4}, 031017 (2014)] in
our cuprate junctions is not feasible, due to Josephson vortices penetration
into the superconducting electrodes which drove the necessary field above the
depairing field.


title:
Correlation Effects on Charge Order and Zero-Gap State in the Organic
  Conductor \alpha-(BEDT-TTF)2I3

abstract:
  The effects of electron correlation in the quasi-two-dimensional organic
conductor \alpha-(BEDT-TTF)2I3 are investigated theoretically by using an
extended Hubbard model with on-site and nearest-neighbor Coulomb interactions.
A variational Monte Carlo method is applied to study its ground-state
properties. We show that there appears a nonmagnetic horizontal-stripe charge
order in which nearest-neighbor correlation functions indicate a tendency
toward a spin-singlet formation on the bonds with large transfer integrals
along the charge-rich stripe. Under uniaxial pressure, a first-order transition
from the nonmagnetic charge order to a zero-gap state occurs. Our results on a
spin correlation length in the charge-ordered state suggest that a spin gap is
almost unaffected by the uniaxial pressure in spite of the suppression of the
charge disproportionation. The relevance of these contrasting behaviors in spin
and charge degrees of freedom to recent experimental observations is discussed.


title: Confirmation of Kramers-Henneberger Atoms

abstract:
  In a remarkable experiment, Eichmann et al. attained unprecedented
acceleration of neutral atoms by strong short-pulse IR laser fields. The
driving mechanism was identified as the ponderomotive force on excited
electrons bound in Rydberg orbits that survive long enough to enable the atoms
to reach the detector. However, the observed velocities lie somewhat above the
theoretical prediction. The systematic discrepancy was attributed to "absolute
laser intensity uncertainties or a slightly non-Gaussian intensity
distribution". Here, we examine the process by transforming to the
Kramers-Henneberger (KH) reference frame. We find that in addition to the
ponderomotive potential there exists a smaller but significant term that comes
from the binding energy of the KH atom. Including this KH term brings the
calculated maximum velocities to a close match with experimental results over
the full range of laser pulse durations.


title: Operator self-similar processes and functional central limit theorems

abstract:
  Let $\{X_k:k\ge1\}$ be a linear process with values in the separable Hilbert
space $L_2(\mu)$ given by $X_k=\sum_{j=0}^\infty(j+1)^{-D}\varepsilon_{k-j}$
for each $k\ge1$, where $D$ is defined by $Df=\{d(s)f(s):s\in\mathbb S\}$ for
each $f\in L_2(\mu)$ with $d:\mathbb S\to\mathbb R$ and
$\{\varepsilon_k:k\in\mathbb Z\}$ are independent and identically distributed
$L_2(\mu)$-valued random elements with $\operatorname E\varepsilon_0=0$ and
$\operatorname E\|\varepsilon_0\|^2<\infty$. We establish sufficient conditions
for the functional central limit theorem for $\{X_k:k\ge1\}$ when the series of
operator norms $\sum_{j=0}^\infty\|(j+1)^{-D}\|$ diverges and show that the
limit process generates an operator self-similar process.


title:
Numerical Convergence Rate for a Diffusive Limit of Hyperbolic Systems:
  p-System with Damping

abstract:
  This paper deals with diffusive limit of the p-system with damping and its
approximation by an Asymptotic Preserving (AP) Finite Volume scheme. Provided
the system is endowed with an entropy-entropy flux pair, we give the
convergence rate of classical solutions of the p-system with damping towards
the smooth solutions of the porous media equation using a relative entropy
method. Adopting a semi-discrete scheme, we establish that the convergence rate
is preserved by the approximated solutions. Several numerical experiments
illustrate the relevance of this result.


title:
A multi-layer market for vehicle-to-grid energy trading in the smart
  grid

abstract:
  In this work, we propose a multi-layer market for vehicle-to-grid energy
trading. In the macro layer, we consider a double auction mechanism, under
which the utility company act as an auctioneer and energy buyers and sellers
interact. This double auction mechanism is strategy-proof and converges
asymptotically. In the micro layer, the aggregators, which are the sellers in
the macro layer, are paid with commissions to sell the energy of plug-in hybrid
electric vehicles (PHEVs) and to maximize their utilities. We analyze the
interaction between the macro and micro layers and study some simplified cases.
Depending on the elasticity of supply and demand, the utility is analyzed under
different scenarios. Simulation results show that our approach can
significantly increase the utility of PHEVs.


title:
Four-body correlation embedded in antisymmetrized geminal power wave
  function

abstract:
  We extend the Coleman's antisymmetrized geminal power (AGP) to develop a wave
function theory that can incorporate up to four-body correlation in a region of
strong correlation. To facilitate the variational determination of the wave
function, the total energy is rewritten in terms of the traces of geminals.
This novel trace formula is applied to a simple model system consisting of one
dimensional Hubbard ring with a site of strong correlation. Our scheme
significantly improves the result obtained by the AGP-CI scheme of Uemura et
al. and also achieves more efficient compression of the degrees of freedom of
the wave function. We regard the result as a step toward a first-principles
wave function theory for a strongly correlated point defect or adsorbate
embedded in an AGP-based mean-field medium.


title: Premelting-Induced Smoothening of the Ice-Vapor Interface

abstract:
  We perform computer simulations of the quasiliquid layer of ice formed at the
ice-vapor interface close to the ice Ih-liquid-vapor triple point of water. Our
study shows that the two distinct surfaces bounding the film behave at small
wavelengths as atomically rough and independent ice-water and water-vapor
interfaces. For long wavelengths, however, the two surfaces couple, large scale
parallel fluctuations are inhibited, and the ice-vapor interface becomes
smooth. Our results could help explain the complex morphology of ice
crystallites.


title:
Existence of weak solutions of an unsteady thermistor problem with
  p-Laplacian type equation

abstract:
  We prove the existence of weak solutions to an unsteady thermistor system
with p-Laplacian type equation for the electrostatic potential, where the
electrical conductivity of the thermistor material is a monotone function of
the electric field density.


title:
How does the spreading speed associated with the Fisher-KPP equation
  depend on random stationary diffusion and reaction terms?

abstract:
  We consider one-dimensional reaction-diffusion equations of Fisher-KPP type
with random stationary ergodic coefficients. A classical result of Freidlin and
Gartner [16] yields that the solutions of the initial value problems associated
with compactly supported initial data admit a linear spreading speed almost
surely. We use in this paper a new characterization of this spreading speed
recently proved in [8] in order to investigate the dependence of this speed
with respect to the heterogeneity of the diffusion and reaction terms. We prove
in particular that adding a reaction term with null average or rescaling the
coefficients by the change of variables x $\rightarrow$ x/L, with L
\textgreater{} 1, speeds up the propagation. From a modelling point of view,
these results mean that adding some heterogeneity in the medium gives a higher
invasion speed, while fragmentation of the medium slows down the invasion.


title:
The Effect of the Schwarz Rearrangement on the Periodic Principal
  Eigenvalue of a Nonsymmetric Operator

abstract:
  This paper is concerned with the periodic principal eigenvalue
$k_\lambda(\mu)$ associated with the operator $- {d^2\over dx^2} - 2\lambda
{d\over dx} - \mu(x) - \lambda^2$ , (1) where $\lambda\in \mathbb{R}$ and $\mu$
is continuous and periodic in $x\in\mathbb{R}$. Our main result is that
$k_\lambda(\mu^*) \le k_\lambda(\mu)$, where $\mu^*$ is the Schwarz
rearrangement of the function $\mu$. From a population dynamics point of view,
using reaction-diffusion modeling, this result means that the fragmentation of
the habitat of an invading population slows down the invasion. We prove that
this property does not hold in higher dimension, if $\mu^*$ is the Steiner
symmetrization of $\mu$. For heterogeneous diffusion and advection, we prove
that increasing the period of the coefficients decreases $k_\lambda$ and we
compute the limit of $k_\lambda$ when the period of the coefficients goes to 0.
Lastly, we prove that, in dimension 1, rearranging the diffusion term decreases
$k_\lambda$. These results rely on some new formula for the periodic principal
eigenvalue of a nonsymmetric operator.


title:
Coexistence in 5G: Analysis of Cross-Interference between OFDM/OQAM and
  Legacy Users

abstract:
  To optimize the use of the spectrum, it is expected that the next generation
of wireless networks (5G) will enable coexistence of newly introduced services
with legacy cellular networks. These new services, like Device-To-Device (D2D)
communication, should require limited synchronization with the legacy cell to
limit the amount of signaling overhead in the network. However, it is known
that Cyclic Prefix-Orthogonal Frequency Division Multiplexing (CP-OFDM) used in
Long Term Evolution-Advanced (LTE-A) is not fit for asynchronous environments.
This has motivated the search for a new waveform, able to enhance coexistence
with CP-OFDM. Namely, it has been widely suggested that new devices could use
OFDM/Offset-Quadrature Amplitude Modulation (OFDM/OQAM) to reduce the
interference they inject to legacy cellular users. However, values of
interference are usually measured at the input antenna of the receiver, based
on the PSD of the interfering signal. We showed in previous works that this
measurement is not representative of the actual interference that is seen after
the demodulation operations. Building on this finding, we provide in this paper
the first exact closed forms of cross-interference between OFDM/OQAM and
CP-OFDM users. Our results prove that using OFDM/OQAM only marginally reduces
interference to legacy users, in contradiction with many results in the
literature.


title:
Square-mean S-asymptotically $\omega$-periodic solution for a stochastic
  fractional evolution equation driven by L\'{e}vy noise with piecewise
  constant argument

abstract:
  In this paper, we introduce some concepts of square-mean S-asymptotically
$\omega$-periodic stochastic processes. Using the stochastic analysis method
and the Banach contraction mapping principle, we establish the existence and
uniqueness results of the mild solution and the square-mean S-asymptotically
$\omega$-periodic solution for a semilinear nonautonomous stochastic fractional
evolution equation driven by L\'{e}vy noise.


title: NLO QCD+EW for V+jets

abstract:
  In this contribution recent results regarding the NLO electroweak corrections
for vector boson production in association with jets are presented. Besides
discussing the phenomenology of the fixed-order results, their corporation in
existing NLO QCD parton shower matched and merged calculations, which can
directly be used in experimental analyses, will be shown.


title: A note on the rank of a restricted Lie algebra

abstract:
  In this short note, we study the rank of a restricted Lie algebra
$(\mathfrak{g},[p])$ and give some applications, which concerns the dimensions
of non-trivial irreducible modules. We also compute the rank of the restricted
contact algebra $K(n)$.


title:
Global stabilization of a Korteweg-de Vries equation with a distributed
  control saturated in L 2 -norm

abstract:
  This article deals with the design of saturated controls in the context of
partial differential equations. It is focused on a Korteweg-de Vries equation,
which is a nonlinear mathematical model of waves on shallow water surfaces. The
aim of this article is to study the influence of a saturating in L 2-norm
distributed control on the well-posedness and the stability of this equation.
The well-posedness is proven applying a Banach fixed point theorem. The proof
of the asymptotic stability of the closed-loop system is tackled with a
Lyapunov function together with a sector condition describing the saturating
input. Some numerical simulations illustrate the stability of the closed-loop
nonlinear partial differential equation.


title:
Renormalization Group Approach to Stability of Two-dimensional
  Interacting Type-II Dirac Fermions

abstract:
  The type-II Weyl/Dirac fermions are a generalization of conventional or
type-I Weyl/Dirac fermions, whose conic spectrum is tilted such that the Fermi
surface becomes lines in two dimensions, and surface in three dimensions rather
than discrete points of the conventional Weyl/Dirac fermions. The
mass-independent renormalization group calculations show that the tilting
parameter decreases monotonically with respect to the length scale, which leads
to a transition from two dimensional type-II Weyl/Dirac fermions to the type-I
ones. Because of the non-trivial Fermi surface, a photon gains a finite mass
partially via the chiral anomaly, leading to the strong screening effect of the
Weyl/Dirac fermions. Consequently, anisotropic type-II Dirac semimetals become
stable against the Coulomb interaction. This work provides deep insight into
the interplay between the geometry of Fermi surface and the Coulomb
interaction.


title: Coexistence of Filter Banks and CP-OFDM: What are the Real Gains?

abstract:
  A coexistence scenario between filter bank (FB) based waveforms and legacy
Cyclic Prefix-Orthogonal Frequency Division Multiplexing (CP-OFDM) is studied.
It is shown that studies available on that matter use a wrong metric to rate
the interference between the coexisting systems. Specifically, it is shown that
even well spectrally localized FB waveforms interfere at a high level with
incumbent CP-OFDM receivers. The presented results invalidate a number of
studies in the literature, which stated that FB based waveforms could be very
efficiently used to insert communications in parts of spectrum left free by
incumbent legacy CP-OFDM users.


title:
Linear extension operators between spaces of Lipschitz maps and optimal
  transport

abstract:
  Motivated by the notion of K-gentle partition of unity introduced in [12] and
the notion of K-Lipschitz retract studied in [17], we study a weaker notion
related to the Kantorovich-Rubinstein transport distance, that we call K-random
projection. We show that K-random projections can still be used to provide
linear extension operators for Lipschitz maps. We also prove that the existence
of these random projections is necessary and sufficient for the existence of
weak* continuous operators. Finally we use this notion to characterize the
metric spaces (X, d) such that the free space F(X) has the bounded
approximation propriety.


title:
Mild Solutions and Harnack Inequality for Functional SPDEs with Dini
  Drift

abstract:
  The existence and uniqueness of the mild solution for a class of functional
SPDEs with multiplicative noise and a locally Dini continuous drift are proved.
In addition, under a reasonable condition the solution is non-explosive.
Moreover, Harnack inequalities are derived for the associated semigroup under
certain global conditions, which is new even in the case without delay.


title:
Evidence of radius inflation in stars approaching the slow-rotator
  sequence

abstract:
  Average stellar radii in open clusters can be estimated from rotation periods
and projected rotational velocities under the assumption of random orientation
of the spin axis. Such estimates are independent of distance, interstellar
absorption, and models, but their validity can be limited by missing data
(truncation) or data that only represent upper/lower limits (censoring). We
present a new statistical analysis method to estimate average stellar radii in
the presence of censoring and truncation. We use theoretical distribution
functions of the projected stellar radius $R \sin i$ to define a likelihood
function in the presence of censoring and truncation. Average stellar radii in
magnitude bins are then obtained by a maximum likelihood parametric estimation
procedure. This method is capable of recovering the average stellar radius
within a few percent with as few as $\approx$ 10 measurements. Here it is
applied for the first time to the dataset available for the Pleiades. We find
an agreement better than $\approx$ 10 percent between the observed $R$ vs $M_K$
relationship and current standard stellar models for 1.2 $\ge M/M_{\odot} \ge$
0.85 with no evident bias. Evidence of a systematic deviation at $2\sigma$
level are found for stars with 0.8 $\ge M/M_{\odot} \ge$ 0.6 approaching the
slow-rotator sequence. Fast-rotators ($P$ < 2 d) agree with standard models
within 15 percent with no systematic deviations in the whole 1.2 $\ge
M/M_{\odot} \ge$ 0.5 range. The evidence found of a possible radius inflation
just below the lower mass limit of the slow-rotator sequence indicates a
possible connection with the transition from the fast to the slow-rotator
sequence.


abstract:
  In this paper, we introduce the concepts of S-asymptotically
$\omega$-periodic solutions in distribution for a class of stochastic
fractional functional differential equations. The existence and uniqueness
results for the S-asymptotically $\omega$-periodic solutions in distribution
are obtained by means of the successive approximation and the Banach
contraction mapping principle, respectively.


title:
Attention-Based Recurrent Neural Network Models for Joint Intent
  Detection and Slot Filling

abstract:
  Attention-based encoder-decoder neural network models have recently shown
promising results in machine translation and speech recognition. In this work,
we propose an attention-based neural network model for joint intent detection
and slot filling, both of which are critical steps for many speech
understanding and dialog systems. Unlike in machine translation and speech
recognition, alignment is explicit in slot filling. We explore different
strategies in incorporating this alignment information to the encoder-decoder
framework. Learning from the attention mechanism in encoder-decoder model, we
further propose introducing attention to the alignment-based RNN models. Such
attentions provide additional information to the intent classification and slot
label prediction. Our independent task models achieve state-of-the-art intent
detection error rate and slot filling F1 score on the benchmark ATIS task. Our
joint training model further obtains 0.56% absolute (23.8% relative) error
reduction on intent detection and 0.23% absolute gain on slot filling over the
independent task models.


title:
Untangling the role of diverse social dimensions in the diffusion of
  microfinance

abstract:
  Ties between individuals on a social network can represent different
dimensions of interactions, and the spreading of information and innovations on
these networks could potentially be driven by some dimensions more than by
others. In this paper we investigate this issue by studying the diffusion of
microfinance within rural India villages and accounting for the whole
multilayer structure of the underlying social networks. We define a new measure
of node centrality, diffusion versatility, and show that this is a better
predictor of microfinance participation rate than previously introduced
measures defined on aggregated single-layer social networks. Moreover, we
untangle the role played by each social dimension and find that the most
prominent role is played by the nodes that are central on layers concerned with
trust, shedding new light on the key triggers of the diffusion of microfinance.


title: Slow dynamics in a quasi-two-dimensional binary complex plasma

abstract:
  Slow dynamics in an amorphous quasi-two-dimensional complex plasma, comprised
of microparticles of two different sizes, was studied experimentally. The
motion of individual particles was observed using video microscopy, and the
self-part of the intermediate scattering function as well as the mean-squared
particle displacement was calculated. The long-time structural relaxation
reveals the characteristic behavior near the glass transition. Our results
suggest that binary complex plasmas can be an excellent model system to study
slow dynamics in classical supercooled fluids.


title:
Vertical dynamics of a horizontally-oscillating active object in a 2D
  granular medium

abstract:
  We use a DEM simulation and analytical considerations to study the dynamics
of a self-energised object, modelled as a disc, oscillating horizontally within
a two-dimesional bed of denser and smaller particles. We find that, for given
material parameters, the immersed object (IO) may rise, sink or not change
depth, depending on the oscillation amplitude and frequency, as well as on the
initial depth. With time, the IO settles at a specific depth that depends on
the oscillation parameters. We construct a phase diagram of this behaviour in
the oscillation frequency and velocity amplitude variable space. We explain the
observed rich behaviour by two competing effects: climbing on particles, which
fill voids opening under the disc, and sinking due to bed fluidisation. We
present a cavity model that allows us to derive analytically general results,
which agree very well with the observations and explain quantitatively the
phase diagram. Our specific analytical results are the following. (i)
Derivation of a critical frequency, $f_c$, above which the IO cannot float up
against gravity. We show that this frequency depends only on the gravitational
acceleration and the IO size. (ii) Derivation of a minimal amplitude,
$A_{min}$, below which the IO cannot rise even if the frequency is below $f_c$.
We show that this amplitude also depends only on the gravitational acceleration
and the IO size. (iii) Derivation of a critical value, $g_c$, of the IO's
acceleration amplitude, below which the IO cannot sink. We show that the value
of $g_c$ depends on the characteristics of both the IO and the granular bed,as
well as on the initial IO's depth.


title:
On a Distributed Computation of Supervisors in Modular Supervisory
  Control

abstract:
  In this paper, we discuss a supervisory control problem of modular
discrete-event systems that allows for a distributed computation of
supervisors. We provide a characterization and an algorithm to compute the
supervisors. If the specification does not satisfy the properties, we make use
of a relaxation of coordination control to compute a sublanguage of the
specification for which the supervisors can be computed in a distributed way.


title:
Deviant Learning Algorithm: Learning Sparse Mismatch Representations
  through Time and Space

abstract:
  Predictive coding (PDC) has recently attracted attention in the neuroscience
and computing community as a candidate unifying paradigm for neuronal studies
and artificial neural network implementations particularly targeted at
unsupervised learning systems. The Mismatch Negativity (MMN) has also recently
been studied in relation to PC and found to be a useful ingredient in neural
predictive coding systems. Backed by the behavior of living organisms, such
networks are particularly useful in forming spatio-temporal transitions and
invariant representations of the input world. However, most neural systems
still do not account for large number of synapses even though this has been
shown by a few machine learning researchers as an effective and very important
component of any neural system if such a system is to behave properly. Our
major point here is that PDC systems with the MMN effect in addition to a large
number of synapses can greatly improve any neural learning system's performance
and ability to make decisions in the machine world. In this paper, we propose a
novel bio-mimetic computational intelligence algorithm -- the Deviant Learning
Algorithm, inspired by these key ideas and functional properties of recent
brain-cognitive discoveries and theories. We also show by numerical experiments
guided by theoretical insights, how our invented bio-mimetic algorithm can
achieve competitive predictions even with very small problem specific data.


title: Knuth's Coherent Presentations of Plactic Monoids of Type A

abstract:
  We construct finite coherent presentations of plactic monoids of type A. Such
coherent presentations express a system of generators and relations for the
monoid extended in a coherent way to give a family of generators of the
relations amongst the relations. Such extended presentations are used for
representations of monoids, in particular, it is a way to describe actions of
monoids on categories. Moreover, a coherent presentation provides the first
step in the computation of a categorical cofibrant replacement of a monoid. Our
construction is based on a rewriting method introduced by Squier that computes
a coherent presentation from a convergent one. We compute a finite coherent
presentation of a plactic monoid from its column presentation that is known to
be finite and convergent. Finally, we show how to reduce this coherent
presentation to a Tietze equivalent one having Knuth's generators.


title:
Statistical Meta-Analysis of Presentation Attacks for Secure
  Multibiometric Systems

abstract:
  Prior work has shown that multibiometric systems are vulnerable to
presentation attacks, assuming that their matching score distribution is
identical to that of genuine users, without fabricating any fake trait. We have
recently shown that this assumption is not representative of current
fingerprint and face presentation attacks, leading one to overestimate the
vulnerability of multibiometric systems, and to design less effective fusion
rules. In this paper, we overcome these limitations by proposing a statistical
meta-model of face and fingerprint presentation attacks that characterizes a
wider family of fake score distributions, including distributions of known and,
potentially, unknown attacks. This allows us to perform a thorough security
evaluation of multibiometric systems against presentation attacks, quantifying
how their vulnerability may vary also under attacks that are different from
those considered during design, through an uncertainty analysis. We empirically
show that our approach can reliably predict the performance of multibiometric
systems even under never-before-seen face and fingerprint presentation attacks,
and that the secure fusion rules designed using our approach can exhibit an
improved trade-off between the performance in the absence and in the presence
of attack. We finally argue that our method can be extended to other biometrics
besides faces and fingerprints.


title:
Joint Online Spoken Language Understanding and Language Modeling with
  Recurrent Neural Networks

abstract:
  Speaker intent detection and semantic slot filling are two critical tasks in
spoken language understanding (SLU) for dialogue systems. In this paper, we
describe a recurrent neural network (RNN) model that jointly performs intent
detection, slot filling, and language modeling. The neural network model keeps
updating the intent estimation as word in the transcribed utterance arrives and
uses it as contextual features in the joint model. Evaluation of the language
model and online SLU model is made on the ATIS benchmarking data set. On
language modeling task, our joint model achieves 11.8% relative reduction on
perplexity comparing to the independent training language model. On SLU tasks,
our joint model outperforms the independent task training model by 22.3% on
intent detection error rate, with slight degradation on slot filling F1 score.
The joint model also shows advantageous performance in the realistic ASR
settings with noisy speech input.


title:
Radio Diagnostics of Electron Acceleration Sites During the Eruption of
  a Flux Rope in the Solar Corona

abstract:
  Electron acceleration in the solar corona is often associated with flares and
the eruption of twisted magnetic structures known as flux ropes. However, the
locations and mechanisms of such particle acceleration during the flare and
eruption are still subject to much investigation. Observing the exact sites of
particle acceleration can help confirm how the flare and eruption are initiated
and how they evolve. Here we use the Atmospheric Imaging Assembly to analyse a
flare and erupting flux rope on 2014-April-18, while observations from the
Nancay Radio Astronomy Facility allows us to diagnose the sites of electron
acceleration during the eruption. Our analysis shows evidence for a pre-formed
flux rope which slowly rises and becomes destabilised at the time of a C-class
flare, plasma jet and the escape of >75 keV electrons from rope center into the
corona. As the eruption proceeds, continued acceleration of electrons with
energies of ~5 keV occurs above the flux rope for a period over 5 minutes. At
flare peak, one site of electron acceleration is located close to the flare
site while another is driven by the erupting flux rope into the corona at
speeds of up to 400 km/s. Energetic electrons then fill the erupting volume,
eventually allowing the flux rope legs to be clearly imaged from radio sources
at 150-445MHz. Following the analysis of Joshi et al. (2015), we conclude that
the sites of energetic electrons are consistent with flux rope eruption via a
tether-cutting or flux cancellation scenario inside a magnetic fan-spine
structure. In total, our radio observations allow us to better understand the
evolution of a flux rope eruption and its associated electron acceleration
sites, from eruption initiation to propagation into the corona.


title: Hub Identification of the Metro Manila Road Network Using PageRank

abstract:
  We attempt to identify the different node hubs of a road network using
PageRank for preparation for possible random terrorist attacks. The robustness
of a road network against such attack is crucial to be studied because it may
cripple its connectivity by simply shutting down these hubs. We show the
important hubs in a road network based on network structure and propose a model
for robustness analysis. By identifying important hubs in a road network,
possible preparation schemes may be done earlier to mitigate random terrorist
attacks, including defense reinforcement and transportation security. A case
study of the Metro Manila road network is also presented. The case study shows
that the most important hubs in the Metro Manila road network are near
airports, piers, major highways and expressways


title:
Multi-instance Dynamic Ordinal Random Fields for Weakly-Supervised Pain
  Intensity Estimation

abstract:
  In this paper, we address the Multi-Instance-Learning (MIL) problem when bag
labels are naturally represented as ordinal variables (Multi--Instance--Ordinal
Regression). Moreover, we consider the case where bags are temporal sequences
of ordinal instances. To model this, we propose the novel Multi-Instance
Dynamic Ordinal Random Fields (MI-DORF). In this model, we treat
instance-labels inside the bag as latent ordinal states. The MIL assumption is
modelled by incorporating a high-order cardinality potential relating bag and
instance-labels,into the energy function. We show the benefits of the proposed
approach on the task of weakly-supervised pain intensity estimation from the
UNBC Shoulder-Pain Database. In our experiments, the proposed approach
significantly outperforms alternative non-ordinal methods that either ignore
the MIL assumption, or do not model dynamic information in target data.


title:
Joint Alignment of Multiple Point Sets with Batch and Incremental
  Expectation-Maximization

abstract:
  This paper addresses the problem of registering multiple point sets.
Solutions to this problem are often approximated by repeatedly solving for
pairwise registration, which results in an uneven treatment of the sets forming
a pair: a model set and a data set. The main drawback of this strategy is that
the model set may contain noise and outliers, which negatively affects the
estimation of the registration parameters. In contrast, the proposed
formulation treats all the point sets on an equal footing. Indeed, all the
points are drawn from a central Gaussian mixture, hence the registration is
cast into a clustering problem. We formally derive batch and incremental EM
algorithms that robustly estimate both the GMM parameters and the rotations and
translations that optimally align the sets. Moreover, the mixture's means play
the role of the registered set of points while the variances provide rich
information about the contribution of each component to the alignment. We
thoroughly test the proposed algorithms on simulated data and on challenging
real data collected with range sensors. We compare them with several
state-of-the-art algorithms, and we show their potential for surface
reconstruction from depth data.


title:
Numerical study of optimal partitioning problems in relation to an
  anisotropic perimeter

abstract:
  We present a ${\Gamma}$-convergence approximation for the total anisotropic
length of a partition. This theoretical result gives rise to a numerical method
which allows the study of minimal partitions with respect to different
anisotropies. We also give a numerical framework for the study of isoperimetric
problems with density.


title: Q-Learning with Basic Emotions

abstract:
  Q-learning is a simple and powerful tool in solving dynamic problems where
environments are unknown. It uses a balance of exploration and exploitation to
find an optimal solution to the problem. In this paper, we propose using four
basic emotions: joy, sadness, fear, and anger to influence a Qlearning agent.
Simulations show that the proposed affective agent requires lesser number of
steps to find the optimal path. We found when affective agent finds the optimal
path, the ratio between exploration to exploitation gradually decreases,
indicating lower total step count in the long run


title:
Application of iterative phase-retrieval algorithms to ARPES orbital
  tomography

abstract:
  Electronic wave functions of planar molecules can be reconstructed via
inverse Fourier transform of angle-resolved photoelectron spectroscopy (ARPES)
data, provided the phase of the electron wave in the detector plane is known.
Since the recorded intensity is proportional to the absolute square of the
Fourier transform of the initial state wave function, information about the
phase distribution is lost in the measurement. It was shown that the phase can
be retrieved in some cases by iterative algorithms using a priori information
about the object such as its size and symmetry. We suggest a more generalized
and robust approach for the reconstruction of molecular orbitals based on
state-of-the-art phase-retrieval algorithms currently used in coherent
diffraction imaging. We draw an analogy between the phase problem in molecular
orbital imaging by ARPES and of that in optical coherent diffraction imaging by
performing an optical analogue experiment on micrometer-sized structures. We
successfully reconstruct amplitude and phase of both the micrometer-sized
objects and a molecular orbital from the optical and photoelectron far-field
intensity distributions, respectively, without any prior information about the
shape of the objects.


title: Localisation in Quantum Field Theory

abstract:
  In nonrelatistic quantum mechanics, Born's principle of localistion is as
follows: For a single particle, if a wave function $\psi_K$ vanishes outside a
spatial region $K$, it is said to be localised in $K$. In particular if a
spatial region $K'$ is disjoint from $K$, a wave function $\psi_{K'}$ localised
in $K'$ is orthogonal to $\psi_K$.
  Such a principle of localisation does not exist compatibly with relativity
and causality in quantum field theory (Newton and Wigner) or interacting point
particles (Currie,Jordan and Sudarshan).It is replaced by symplectic
localisation of observables as shown by Brunetti, Guido and Longo, Schroer and
others. This localisation gives a simple derivation of the spin-statistics
theorem and the Unruh effect, and shows how to construct quantum fields for
anyons and for massless particles with `continuous' spin.
  This review outlines the basic principles underlying symplectic localisation
and shows or mentions its deep implications. In particular, it has the
potential to affect relativistic quantum information theory and black hole
physics.


title:
Importance of the H2 abundance in protoplanetary disk ices for the
  molecular layer chemical composition

abstract:
  Protoplanetary disks are the target of many chemical studies (both
observational and theoretical) as they contain the building material for
planets. Their large vertical and radial gradients in density and temperature
make them challenging objects for chemical models. In the outer part of these
disks, the large densities and low temperatures provide a particular
environment where the binding of species onto the dust grains can be very
efficient and can affect the gas-phase chemical composition.
  We attempt to quantify to what extent the vertical abundance profiles and the
integrated column densities of molecules predicted by a detailed gas-grain code
are affected by the treatment of the molecular hydrogen physisorption at the
surface of the grains. We performed three different models using the Nautilus
gas-grain code. One model uses a H2 binding energy on the surface of water (440
K) and produces strong sticking of H2. Another model uses a small binding
energy of 23 K (as if there were already a monolayer of H2), and the sticking
of H$_2$ is almost negligible. Finally, the remaining model is an intermediate
solution known as the encounter desorption mechanism. We show that the
efficiency of molecular hydrogen binding (and thus its abundance at the surface
of the grains) can have a quantitative effect on the predicted column densities
in the gas phase of major species such as CO, CS, CN, and HCN.


title:
OpenTripPlanner, OpenStreetMap, General Transit Feed Specification:
  Tools for Disaster Relief and Recovery

abstract:
  Open Trip Planner was identified as the most promising open source
multi-modal trip planning software. Open Street Map, which provides mapping
data to Open Trip Planner, is one of the most well-known open source
international repository of geographic data. General Transit Feed
Specification, which provides transportation data to Open Trip Planner, has
been the standard for describing transit systems and platform for numerous
applications. Together, when used to implement an instance of Open Trip
Planner, these software has been helping in traffic decongestion all over the
world by assisting commuters to shift from using private transportation modes
to public ones. Their potential however goes beyond providing multi-modal
public transportation routes. This paper aims to first discuss the researchers'
experience in implementing a public transportation route planner for the
purpose of traffic decongestion.The researchers would examine the prospective
of using the system for disaster preparedness and recovery and concrete ways on
how to realize them.


title:
Covariant open bosonic string field theory on multiple D-branes in the
  proper-time gauge

abstract:
  We construct a covariant open bosonic string field theory on multiple
D-branes, which reduces to a non-Abelian group Yang-Mills gauge theory in the
zero-slope limit. Making use of the first quantized open bosonic string in the
proper time gauge, we convert the string amplitudes given by the Polyakov path
integrals on string world sheets into those of the second quantized theory. The
world sheet diagrams generated by the constructed open string field theory are
planar in contrast to those of the Witten's cubic string field theory. However,
the constructed string field theory is yet equivalent to the Witten's cubic
string field theory. Having obtained planar diagrams, we may adopt the
light-cone string field theory technique to calculate the multi-string
scattering amplitudes with an arbitrary number of external strings. We examine
in detail the three-string vertex diagram and the effective four-string vertex
diagrams generated perturbatively by the three-string vertex at tree level. In
the zero-slope limit, the string scattering amplitudes are identified precisely
as those of non-Abelian Yang-Mills gauge theory if the external states are
chosen to be massless vector particles.


title: Goldstone-Type Pseudoscalar Mesons: Instantaneous Bethe-Salpeter Models

abstract:
  A nontrivial instantaneous variant of the Bethe-Salpeter formalism allows us
to discuss massless pseudoscalar mesons from a configuration-space-potential
point of view.


title: Multi Exit Configuration of Mesoscopic Pedestrian Simulation

abstract:
  A mesoscopic approach to modeling pedestrian simulation with multiple exits
is proposed in this paper. A floor field based on Qlearning Algorithm is used.
Attractiveness of exits to pedestrian typically is based on shortest path.
However, several factors may influence pedestrian choice of exits. Scenarios
with multiple exits are presented and effect of Q-learning rewards system on
navigation is investigated


title: Can decay be ascribed to classical noise?

abstract: No.


title:
Holographic dark energy in Brans-Dicke theory with logarithmic form of
  scalar field

abstract:
  In this paper, an interacting holographic dark energy model with Hubble
horizon as an infra-red cut-off is considered in the framework of Brans-Dicke
theory. We propose a logarithmic form $\phi \propto ln(\alpha+\beta a)$ of the
Brans-Dicke scalar field to alleviate the problems of interacting holographic
dark energy models in Brans-Dicke theory. We find that the equation of state
parameter $w_h$ and deceleration parameter $q$ are negative in the early time
which shows the early time inflation. During the evolution the sign of
parameter $q$ changes from negative to positive which means that the Universe
expands with decelerated rate whereas the sign of $w_h$ may change or remain
negative throughout the evolution depending on the values of parameters. It is
also observed that $w_h$ may cross the phantom divide line in the late time
evolution. The sign of $q$ changes from positive to negative during late time
of evolution which explains the late time accelerated expansion of the
Universe. Thus, we present a unified model of holographic dark energy which
explains the early time acceleration (inflation), medieval time deceleration
and late time acceleration. We also discuss the cosmic coincidence problem. We
obtain a time-varying density ratio of holographic dark energy to dark matter
which is a constant of order one ($r\sim \mathcal{O}(1)$) during early and late
time evolution. Therefore, our model successfully resolves the cosmic
coincidence problem.


title:
Photoexcitation of electron wave packets in quantum spin Hall edge
  states: effects of chiral anomaly from a localised electric pulse

abstract:
  We show that, when a spatially localised electric pulse is applied at the
edge of a quantum spin Hall system, electron wavepackets of the helical states
can be photoexcited by purely intra-branch electrical transitions, without
invoking the bulk states or the magnetic Zeeman coupling. In particular, as
long as the electric pulse remains applied, the photoexcited densities lose
their character of right- and left-movers, whereas after the ending of the
pulse they propagate in opposite directions without dispersion, i.e.
maintaining their space profile unaltered. Notably we find that, while the
momentum distribution of the photoexcited wave packets depends on the
temperature $T$ and the chemical potential $\mu$ of the initial equilibrium
state and displays a non-linear behavior on the amplitude of the applied pulse,
in the mesoscopic regime the space profile of the wave packets is independent
of $T$ and $\mu$. Instead, it depends purely on the applied electric pulse, in
a linear manner, as a signature of the chiral anomaly characterising massless
Dirac electrons. We also discuss how the photoexcited wave packets can be
tailored with the electric pulse parameters, for both low and finite
frequencies.


title: A Lightweight Approach to Performance Portability with targetDP

abstract:
  Leading HPC systems achieve their status through use of highly parallel
devices such as NVIDIA GPUs or Intel Xeon Phi many-core CPUs. The concept of
performance portability across such architectures, as well as traditional CPUs,
is vital for the application programmer. In this paper we describe targetDP, a
lightweight abstraction layer which allows grid-based applications to target
data parallel hardware in a platform agnostic manner. We demonstrate the
effectiveness of our pragmatic approach by presenting performance results for a
complex fluid application (with which the model was co-designed), plus a
separate lattice QCD particle physics code. For each application, a single
source code base is seen to achieve portable performance, as assessed within
the context of the Roofline model. TargetDP can be combined with MPI to allow
use on systems containing multiple nodes: we demonstrate this through provision
of scaling results on traditional and GPU-accelerated large scale
supercomputers.


title: SimCADO - an instrument data simulator package for MICADO at the E-ELT

abstract:
  MICADO will be the first-light wide-field imager for the European Extremely
Large Telescope (E-ELT) and will provide difiraction limited imaging (7mas at
1.2mm) over a ~53 arcsecond field of view. In order to support various
consortium activities we have developed a first version of SimCADO: an
instrument simulator for MICADO. SimCADO uses the results of the detailed
simulation efforts conducted for each of the separate consortium-internal work
packages in order to generate a model of the optical path from source to
detector readout. SimCADO is thus a tool to provide scientific context to both
the science and instrument development teams who are ultimately responsible for
the final design and future capabilities of the MICADO instrument. Here we
present an overview of the inner workings of SimCADO and outline our plan for
its further development.


title:
Methods for calculation of the coupling coefficients in the Coupling
  Cavity Model of arbitrary chain of resonators

abstract:
  We present the short description of the methods for calculation of the
coupling coefficients in the Coupling Cavity Model of arbitrary chain of
resonators. In the first part the procedure that is based on the Mode Matching
Method is given. Then we present the new method that used only one eigen
vector.


title:
Existence and stability of almost periodic solutions to impulsive
  stochastic differential evolution equations with infinite delay

abstract:
  In this paper, we investigate a class of nonlinear impulsive stochastic
differential evolution equations with infinite delay in Banach space. Based on
the Krasnoselskii's fixed point theorem, sufficient conditions of the existence
of the square mean piecewise almost periodic solutions to this type of
equations are derived. Moreover, the exponential stability of the square mean
piecewise almost periodic solution is investigated.


title:
Joint Beamforming and Feature Detection for Enhanced Visualization of
  Spinal Bone Surfaces in Ultrasound Images

abstract:
  We propose a framework for extracting the bone surface from B-mode images
employing the eigenspace minimum variance (ESMV) beamformer and a ridge
detection method. We show that an ESMV beamformer with a rank-1 signal subspace
can preserve the bone anatomy and enhance the edges, despite an image which is
less visually appealing due to some speckle pattern distortion. The beamformed
images are post-processed using the phase symmetry (PS) technique. We validate
this framework by registering the ultrasound images of a vertebra (in a water
bath) against the corresponding Computed Tomography (CT) dataset. The results
show a bone localization error in the same order of magnitude as the standard
delay-and-sum (DAS) technique, but with approximately 20% smaller standard
deviation (STD) of the image intensity distribution around the bone surface.
This indicates a sharper bone surface detection. Further, the noise level
inside the bone shadow is reduced by 60%. In in-vivo experiments, this
framework is used for imaging the spinal anatomy. We show that PS images
obtained from this beamformer setup have sharper bone boundaries in comparison
with the standard DAS ones, and they are reasonably well separated from the
surrounding soft tissue.


title: A Markov Chain based Ensemble Method for Crowdsourced Clustering

abstract:
  In presence of multiple clustering solutions for the same dataset, a
clustering ensemble approach aims to yield a single clustering of the dataset
by achieving a consensus among the input clustering solutions. The goal of this
consensus is to improve the quality of clustering. It has been seen that there
are some image clustering tasks that cannot be easily solved by computer. But
if these images can be outsourced to the general people (crowd workers) to
group them based on some similar features, and opinions are collected from
them, then this task can be managed in an efficient manner and time effective
way. In this work, the power of crowd has been used to annotate the images so
that multiple clustering solutions can be obtained from them and thereafter a
Markov chain based ensemble method is introduced to make a consensus of
multiple clustering solutions.


title: The Morse index of the critical catenoid

abstract:
  We show that the rotationally symmetric free boundary minimal catenoid in the
unit ball in $\Bbb{R}^3$ has Morse index equal to $4$.


title:
Stability in terms of two measures of solutions to stochastic partial
  differential delay equations with switching

abstract:
  In this paper, the problem of stability in terms of two measures is
considered for a class of stochastic partial differential delay equations with
switching. Sufficient conditions for stability in terms of two measures are
obtained based on the technique of constructing a proper approximating strong
solution system and carrying out a limiting type of argument to pass on
stability of strong solutions to mild ones obtained by Bao, Truman and Yuan [
J. Bao, A. Truman,C. Yuan, Stability in distribution of mild solutions to
stochastic partial differential delay equations with jumps, Proc. R. Soc. A,
465, 2111-2134 (2009)]. In particular, the stochastic stability under the
fixed-index sequence monotonicity condition and under the average dwell-time
switching are considered.


title: Nanoscale thermal imaging of dissipation in quantum systems

abstract:
  Energy dissipation is a fundamental process governing the dynamics of
physical, chemical, and biological systems. It is also one of the main
characteristics distinguishing quantum and classical phenomena. In condensed
matter physics, in particular, scattering mechanisms, loss of quantum
information, or breakdown of topological protection are deeply rooted in the
intricate details of how and where the dissipation occurs. Despite its vital
importance the microscopic behavior of a system is usually not formulated in
terms of dissipation because the latter is not a readily measureable quantity
on the microscale. Although nanoscale thermometry is gaining much recent
interest, the existing thermal imaging methods lack the necessary sensitivity
and are unsuitable for low temperature operation required for study of quantum
systems. Here we report a superconducting quantum interference nano-thermometer
device with sub 50 nm diameter that resides at the apex of a sharp pipette and
provides scanning cryogenic thermal sensing with four orders of magnitude
improved thermal sensitivity of below 1 {\mu}K/Hz1/2. The non-contact
non-invasive thermometry allows thermal imaging of very low nanoscale energy
dissipation down to the fundamental Landauer limit of 40 fW for continuous
readout of a single qubit at 1 GHz at 4.2 K. These advances enable observation
of dissipation due to single electron charging of individual quantum dots in
carbon nanotubes and reveal a novel dissipation mechanism due to resonant
localized states in hBN encapsulated graphene, opening the door to direct
imaging of nanoscale dissipation processes in quantum matter.

categories: cond-mat.mes-hall cond-mat.mtrl-sci cond-mat.supr-con physics.ins-det


title: Stochastic Monotonicity of Markovian Multi-class Queueing Networks

abstract:
  Multi-class queueing networks (McQNs) extend the classical concept of Jackson
network by allowing jobs of different classes to visit the same server. While
such a generalization seems rather natural, from a structural perspective there
is a significant gap between the two concepts. Nice analytical features of
Jackson networks, such as stability conditions, product-form equilibrium
distributions, and stochastic monotonicity do not immediately carry over to the
multi-class framework. The aim of this paper is to shed some light on this
structural gap, focusing on monotonicity properties. To this end, we introduce
and study a class of Markov processes, which we call \emph{Q-processes},
modeling the time evolution of the network configuration of any open,
work-conservative McQN having exponential service times and {Poisson input}. We
define a new monotonicity notion tailored for this class of processes. Our main
result is that we show monotonicity for a large class of McQN models, covering
virtually all instances of practical interest. This leads to interesting
properties which are commonly encountered for `traditional' queueing processes,
such as (i)~monotonicity with respect to external arrival rates and
(ii)~star-convexity of the stability region (with respect to the external
arrival rates); such properties are well known for Jackson networks, but had
not been established at this level of generality. This research was partly
motivated by the recent development of a simulation-based method which allows
one to numerically determine the stability region of a McQN parametrized in
terms of the arrival rates vector.


title:
Nonstandard transitions in the Kuramoto model: A role of asymmetry in
  natural frequency distributions

abstract:
  We study transitions in the Kuramoto model by shedding light on asymmetry in
the natural frequency distribution, which has been assumed to be symmetric in
many previous studies. The asymmetry brings two nonstandard bifurcation
diagrams, with the aid of bimodality. The first diagram consists of stationary
states, and has the standard continuous synchronization transition and a
subsequent discontinuous transition as the coupling strength increases. Such a
bifurcation diagram has been also reported in a variant model, which breaks the
odd symmetry of the coupling function by introducing the phase lag. The second
diagram includes the oscillatory state emerging from the partially synchronized
state and followed by a discontinuous transition. This diagram is firstly
revealed in this study. The two bifurcation diagrams are obtained by employing
the Ott-Antonsen ansatz, and are verified by direct $N$-body simulations. We
conclude that the asymmetry in distribution, with the bimodality, plays a
similar role to the phase lag, and diversifies the transitions.


title: A Non-linear GPU Thread Map for Triangular Domains

abstract:
  There is a stage in the GPU computing pipeline where a grid of thread-blocks,
in \textit{parallel space}, is mapped onto the problem domain, in \textit{data
space}. Since the parallel space is restricted to a box type geometry, the
mapping approach is typically a $k$-dimensional bounding box (BB) that covers a
$p$-dimensional data space. Threads that fall inside the domain perform
computations while threads that fall outside are discarded at runtime. In this
work we study the case of mapping threads efficiently onto triangular domain
problems and propose a block-space linear map $\lambda(\omega)$, based on the
properties of the lower triangular matrix, that reduces the number of
unnnecessary threads from $\mathcal{O}(n^2)$ to $\mathcal{O}(n)$. Performance
results for global memory accesses show an improvement of up to $18\%$ with
respect to the \textit{bounding-box} approach, placing $\lambda(\omega)$ on
second place below the \textit{rectangular-box} approach and above the
\textit{recursive-partition} and \textit{upper-triangular} approaches. For
shared memory scenarios $\lambda(\omega)$ was the fastest approach achieving
$7\%$ of performance improvement while preserving thread locality. The results
obtained in this work make $\lambda(\omega)$ an interesting map for efficient
GPU computing on parallel problems that define a triangular domain with or
without neighborhood interactions. The extension to tetrahedral domains is
analyzed, with applications to triplet-interaction n-body applications.


title:
Towards Learning and Verifying Invariants of Cyber-Physical Systems by
  Code Mutation

abstract:
  Cyber-physical systems (CPS), which integrate algorithmic control with
physical processes, often consist of physically distributed components
communicating over a network. A malfunctioning or compromised component in such
a CPS can lead to costly consequences, especially in the context of public
infrastructure. In this short paper, we argue for the importance of
constructing invariants (or models) of the physical behaviour exhibited by CPS,
motivated by their applications to the control, monitoring, and attestation of
components. To achieve this despite the inherent complexity of CPS, we propose
a new technique for learning invariants that combines machine learning with
ideas from mutation testing. We present a preliminary study on a water
treatment system that suggests the efficacy of this approach, propose
strategies for establishing confidence in the correctness of invariants, then
summarise some research questions and the steps we are taking to investigate
them.


title:
First search for dark matter annihilations in the Earth with the IceCube
  Detector

abstract:
  We present the results of the first IceCube search for dark matter
annihilation in the center of the Earth. Weakly Interacting Massive Particles
(WIMPs), candidates for dark matter, can scatter off nuclei inside the Earth
and fall below its escape velocity. Over time the captured WIMPs will be
accumulated and may eventually self-annihilate. Among the annihilation products
only neutrinos can escape from the center of the Earth. Large-scale neutrino
telescopes, such as the cubic kilometer IceCube Neutrino Observatory located at
the South Pole, can be used to search for such neutrino fluxes.
  Data from 327 days of detector livetime during 2011/ 2012 were analyzed. No
excess beyond the expected background from atmospheric neutrinos was detected.
The derived upper limits on the annihilation rate of WIMPs in the Earth and the
resulting muon flux are an order of magnitude stronger than the limits of the
last analysis performed with data from IceCube's predecessor AMANDA. The limits
can be translated in terms of a spin-independent WIMP-nucleon cross section.
For a WIMP mass of 50 GeV this analysis results in the most restrictive limits
achieved with IceCube data.


title: Axiomatizing Category Theory in Free Logic

abstract:
  Starting from a generalization of the standard axioms for a monoid we present
a stepwise development of various, mutually equivalent foundational axiom
systems for category theory. Our axiom sets have been formalized in the
Isabelle/HOL interactive proof assistant, and this formalization utilizes a
semantically correct embedding of free logic in classical higher-order logic.
The modeling and formal analysis of our axiom sets has been significantly
supported by series of experiments with automated reasoning tools integrated
with Isabelle/HOL. We also address the relation of our axiom systems to
alternative proposals from the literature, including an axiom set proposed by
Freyd and Scedrov for which we reveal a technical issue (when encoded in free
logic where free variables range over defined and undefined objects): either
all operations, e.g. morphism composition, are total or their axiom system is
inconsistent. The repair for this problem is quite straightforward, however.


title: Harnessing Poly(ionic liquid)s for Sensing Applications

abstract:
  The interest in poly(ionic liquids) for sensing applications are derived from
their strong interactions to a variety of analytes. By combining the desirable
mechanical properties of polymers with the physical and chemical properties of
ILs, new materials can be created. The tunable nature of both ionic liquids and
polymers allows for incredible diversity, which is exemplified in their broad
applicability. In this article we examine the new field of poly(ionic liquid)
sensors by providing a detailed look at the current state-of-the-art sensing
devices for solvents, gasses, biomolecules, pH, and anions.