title:
The insight into the dark side. I. The pitfalls of the dark halo
  parameters estimation

abstract:
  We examined the reliability of estimates of pseudoisothermal, Burkert and NFW
dark halo parameters for the methods based on the mass-modelling of the
rotation curves.To do it we constructed the $\chi^2$ maps for the grid of the
dark matter halo parameters for a sample of 14 disc galaxies with high quality
rotation curves from THINGS. We considered two variants of models in which: a)
the mass-to-light ratios of disc and bulge were taken as free parameters, b)
the mass-to-light ratios were fixed in a narrow range according to the models
of stellar populations.
  To reproduce the possible observational features of the real galaxies we made
tests showing that the parameters of the three halo types change critically in
the cases of a lack of kinematic data in the central or peripheral areas and
for different spatial resolutions.
  We showed that due to the degeneracy between the central densities and the
radial scales of the dark haloes there are considerable uncertainties of their
concentrations estimates. Due to this reason it is also impossible to draw any
firm conclusion about universality of the dark halo column density based on
mass-modelling of even a high quality rotation curve. The problem is not solved
by fixing the density of baryonic matter.
  In contrast, the estimates of dark halo mass within optical radius are much
more reliable. We demonstrated that one can evaluate successfully the halo mass
using the pure best-fitting method without any restrictions on the
mass-to-light ratios.


title:
Entanglement of remote material qubits through nonexciting interaction
  with single photons

abstract:
  We propose a scheme to entangle multiple material qubits through interaction
with single photons via non-exciting processes associated with strongly
coupling systems. The basic idea is based on the material state dependent
reflection and transmission for the input photons. Thus, the material qubits in
several systems can be entangled when one photon interacts with each system in
cascade and the photon paths are mixed by the photon detection. The character
of non-exciting of the material qubits does not change the state of material
qubit and thus ensures the possibility of purifying entangled states by using
more photons under realistic imperfect parameters. It also guarantees directly
scaling up the scheme to entangle more qubits. Detailed analysis of fidelity
and success probability of the scheme in the frame of an optical
Fabry-P\'{e}rot (FP) cavity based strongly coupling system is presented. It is
shown that a two-qubit entangled state with fidelity above 0.99 is promised
with only two photons by using currently feasible experimental parameters. Our
scheme can also be directly implemented on other strongly coupled system.


title: Channel Estimation for Diffusive Molecular Communications

abstract:
  In molecular communication (MC) systems, the \textit{expected} number of
molecules observed at the receiver over time after the instantaneous release of
molecules by the transmitter is referred to as the channel impulse response
(CIR). Knowledge of the CIR is needed for the design of detection and
equalization schemes. In this paper, we present a training-based CIR estimation
framework for MC systems which aims at estimating the CIR based on the
\textit{observed} number of molecules at the receiver due to emission of a
\textit{sequence} of known numbers of molecules by the transmitter. Thereby, we
distinguish two scenarios depending on whether or not statistical channel
knowledge is available. In particular, we derive maximum likelihood (ML) and
least sum of square errors (LSSE) estimators which do not require any knowledge
of the channel statistics. For the case, when statistical channel knowledge is
available, the corresponding maximum a posteriori (MAP) and linear minimum mean
square error (LMMSE) estimators are provided. As performance bound, we derive
the classical Cramer Rao (CR) lower bound, valid for any unbiased estimator,
which does not exploit statistical channel knowledge, and the Bayesian CR lower
bound, valid for any unbiased estimator, which exploits statistical channel
knowledge. Finally, we propose optimal and suboptimal training sequence designs
for the considered MC system. Simulation results confirm the analysis and
compare the performance of the proposed estimation techniques with the
respective CR lower bounds.


title:
Model-independent limits and constraints on extended theories of gravity
  from cosmic reconstruction techniques

abstract:
  The onset of dark energy domination depends on the particular gravitational
theory driving the cosmic evolution. Model independent techniques are crucial
to test both the present $\Lambda$CDM cosmological paradigm and alternative
theories, making the least possible number of assumptions about the Universe.
In this paper we investigate whether cosmography is able to distinguish between
different gravitational theories, by determining bounds on model parameters for
three different extensions of General Relativity, i.e. $k-$essence, $F(T)$ and
$f(R)$ theories. We expand each class of theories in powers of redshift $z$
around the present time, making no additional assumptions. This procedure is an
extension of previous work and can be seen as the most general approach for
testing extended theories of gravity with cosmography. In the case of $F(T)$
and $f(R)$ theories, we show that some assumptions on model parameters often
made in previous works are superfluous or unjustified. We use data from the
Union2.1 SN catalogue, BAO data and $H(z)$ differential age compilations, which
probe cosmology on different scales. We perform a Monte Carlo analysis using a
Metropolis-Hastings algorithm with a Gelman-Rubin convergence criterion,
reporting 1-$\sigma$ and 2-$\sigma$ confidence levels. We perform two distinct
fits, first taking only data at $z<1$ and then for all $z$. We obtain the
corresponding parameter intervals, and find that the data is compatible the
$\Lambda$CDM limit of all three theories at the 1-$\sigma$ level, while still
compatible with quite a large portion of parameter space. We compare our
results to the truncated $\Lambda$CDM paradigm, showing that the permitted
regions of coefficients are significantly modified and in general widened
compared to values reported in the existing literature. Finally, we test the
extended theories through the Bayesian selection criteria AIC and BIC.


title: Admissible decomposition for spectral multipliers on Gaussian L^p

abstract:
  This paper concerns harmonic analysis of the Ornstein--Uhlenbeck operator L
on the Euclidean space. We examine the method of decomposing a spectral
multiplier \phi(L) into three parts according to the notion of admissibility,
which quantifies the doubling behaviour of the underlying Gaussian measure
\gamma. We prove that the above-mentioned admissible decomposition is bounded
in L^p(\gamma) for 1 < p \leq 2 in a certain sense involving the Gaussian
conical square function. The proof relates admissibility with E. Nelson's
hypercontractivity theorem in a novel way.


title:
Self-paced Learning for Weakly Supervised Evidence Discovery in
  Multimedia Event Search

abstract:
  Multimedia event detection has been receiving increasing attention in recent
years. Besides recognizing an event, the discovery of evidences (which is
refered to as "recounting") is also crucial for user to better understand the
searching result. Due to the difficulty of evidence annotation, only limited
supervision of event labels are available for training a recounting model. To
deal with the problem, we propose a weakly supervised evidence discovery method
based on self-paced learning framework, which follows a learning process from
easy "evidences" to gradually more complex ones, and simultaneously exploit
more and more positive evidence samples from numerous weakly annotated video
segments. Moreover, to evaluate our method quantitatively, we also propose two
metrics, \textit{PctOverlap} and \textit{F1-score}, for measuring the
performance of evidence localization specifically. The experiments are
conducted on a subset of TRECVID MED dataset and demonstrate the promising
results obtained by our method.


title:
Caching Policy Toward Maximal Success Probability and Area Spectral
  Efficiency of Cache-enabled HetNets

abstract:
  In this paper, we investigate the optimal caching policy respectively
maximizing the success probability and area spectral efficiency (ASE) in a
cache-enabled heterogeneous network (HetNet) where a tier of multi-antenna
macro base stations (MBSs) is overlaid with a tier of helpers with caches.
Under the probabilistic caching framework, we resort to stochastic geometry
theory to derive the success probability and ASE. After finding the optimal
caching policies, we analyze the impact of critical system parameters and
compare the ASE with traditional HetNet where the MBS tier is overlaid by a
tier of pico BSs (PBSs) with limited-capacity backhaul. Analytical and
numerical results show that the optimal caching probability is less skewed
among helpers to maximize the success probability when the ratios of
MBS-to-helper density, MBS-to-helper transmit power, user-to-helper density, or
the rate requirement are small, but is more skewed to maximize the ASE in
general. Compared with traditional HetNet, the helper density is much lower
than the PBS density to achieve the same target ASE. The helper density can be
reduced by increasing cache size. With given total cache size within an area,
there exists an optimal helper node density that maximizes the ASE.


title:
Existence of multi-peak solutions for a class of quasilinear problems in
  Orlicz-Sobolev spaces

abstract:
  The aim of this work is to establish the existence of multi-peak solutions
for the following class of quasilinear problems \[ -
\mbox{div}\big(\epsilon^{2}\phi(\epsilon|\nabla u|)\nabla u\big) + V(x)\phi(|
u|)u = f(u)\quad \mbox{in} \quad \mathbb{R}^{N}, \] where $\epsilon$ is a
positive parameter, $ N\geq 2$, $V, f$ are continuous functions satisfying some
technical conditions and $\phi$ is a $C^{1}$-function.


title: Intertwined nematic orders in a frustrated ferromagnet

abstract:
  We investigate the quantum phases of the frustrated spin-$\frac{1}{2}$
$J_1$-$J_2$-$J_3$ Heisenberg model on the square lattice with ferromagnetic
$J_1$ and antiferromagnetic $J_2$ and $J_3$ interactions. Using the
pseudo-fermion functional renormalization group technique, we find an
intermediate paramagnetic phase located between classically ordered
ferromagnetic, stripy antiferromagnetic, and incommensurate spiral phases. We
observe that quantum fluctuations lead to significant shifts of the spiral
pitch angles compared to the classical limit. By computing the response of the
system with respect to various spin rotation and lattice symmetry-breaking
perturbations, we identify a complex interplay between different nematic spin
states in the paramagnetic phase. While retaining time-reversal invariance,
these phases either break spin-rotation symmetry, lattice-rotation symmetry, or
a combination of both. We therefore propose the $J_1$-$J_2$-$J_3$ Heisenberg
model on the square lattice as a paradigmatic example where different
intimately connected types of nematic orders emerge in the same model.


title:
Mapping the orbital structure of impurity bound states in a
  superconductor

abstract:
  A magnetic atomic impurity inside a superconductor locally distorts
superconductivity. They scatter Cooper pairs as a potential with broken
time-reversal symmetry, what leads to localized bound states with subgap
excitation energies, named hereon Shiba states. Most conventional approaches to
study Shiba states treat magnetic impurities as point scatterers with an
isotropic exchange interaction, while the complex internal structure of
magnetic impurities is usually neglected. Here, we show that the number and the
shape of Shiba states are correlated to the spin-polarized atomic orbitals of
the impurity, hybridized with the superconducting host, as supported by Density
Functional Theory simulations. Using high-resolution scanning tunneling
spectroscopy, we spatially map the five Shiba excitations found on sub-surface
chromium atoms in Pb(111), resolving both their particle and hole components.
While the maps of particle components resemble the \textit{d} orbitals of
embedded Cr atoms, the hole components differ strongly from them. The orbital
fingerprints of Shiba states thus unveil the magnetic ground state of the
impurity, and identify scattering channels and interactions, all valuable tools
for designing atomic-scale superconducting devices.


title:
The Braess Paradox in a network of totally asymmetric exclusion
  processes

abstract:
  We study the Braess paradox in the transport network as originally proposed
by Braess with totally asymmetric exclusion processes (TASEPs) on the edges.
The Braess paradox describes the counterintuitive situation in which adding an
edge to a road network leads to a user optimum with higher travel times for all
network users. Travel times on the TASEPs are nonlinear in the density, and
jammed states can occur due to the microscopic exclusion principle, leading to
a more realistic description of trafficlike transport on the network than in
previously studied linear macroscopic mathematical models. Furthermore, the
stochastic dynamics allows us to explore the effects of fluctuations on network
performance. We observe that for low densities, the added edge leads to lower
travel times. For slightly higher densities, the Braess paradox occurs in its
classical sense. At intermediate densities, strong fluctuations in the travel
times dominate the system's behavior due to links that are in a domain-wall
state. At high densities, the added link leads to lower travel times. We
present a phase diagram that predicts the system's state depending on the
global density and crucial path-length ratios.


title:
Group actions, deformations, polygroup extensions, and group
  presentations

abstract:
  Generalizing classical extension theory, we solve a Schreier-type extension
problem for polygroups by groups. As a consequence, we obtain a method for
computing a presentation for a group from its action on a set. The usefulness
of this method is illustrated by deriving explicit presentations for the groups
$GL_2$ over valuation rings and over valued fields, for the groups $SL_3$ over
arbitrary fields, as well as for the five Mathieu groups. Moreover, we sketch
some aspects of a new deformation technique for groups, their actions, and
presentations, and apply it to compute presentations for the sharply
$3$-transitive Zassenhaus groups $M(q^2)$ (in the notation of Huppert and
Blackburn) for any odd prime power $q$. This computation serves to demonstrate
how suitable deformation of groups and their actions interacts with, and
thereby enhances, the presentation method.


title:
Shubnikov-de Haas oscillations and electronic correlations in the
  layered organic metal $\kappa$-(BETS)$_2$Mn[N(CN)$_2$]$_3$

abstract:
  We present magnetoresistance studies of the quasi-two-dimensional organic
conductor $\kappa$-(BETS)$_2$Mn[N(CN)$_2$]$_3$, where BETS stands for
bis\-(ethylene\-dithio)\-tetra\-selena\-fulvalene. Under a moderate pressure of
1.4\,kbar, required for stabilizing the metallic ground state, Shubnikov - de
Haas oscillations, associated with a classical and a magnetic-breakdown
cyclotron orbits on the cylindrical Fermi surface, have been found at fields
above 10\,T. The effective cyclotron masses evaluated from the temperature
dependence of the oscillation amplitudes reveal strong renormalization due to
many-body interactions. The analysis of the relative strength of the
oscillations corresponding to the different orbits and its dependence on
magnetic field suggests an enhanced role of electron-electron interactions on
flat parts of the Fermi surface.


title:
Dynamic response functions and helical gaps in interacting Rashba
  nanowires with and without magnetic fields

abstract:
  A partially gapped spectrum due to the application of a magnetic field is one
of the main probes of Rashba spin-orbit coupling in nanowires. Such a "helical
gap" manifests itself in the linear conductance, as well as in dynamic response
functions such as the spectral function, the structure factor, or the
tunnelling density of states. In this paper, we investigate theoretically the
signature of the helical gap in these observables with a particular focus on
the interplay between Rashba spin-orbit coupling and electron-electron
interactions. We show that in a quasi-one-dimensional wire, interactions can
open a helical gap even without magnetic field. We calculate the dynamic
response functions using bosonization, a renormalization group analysis, and
the exact form factors of the emerging sine-Gordon model. For special
interaction strengths, we verify our results by refermionization. We show how
the two types of helical gaps, caused by magnetic fields or interactions, can
be distinguished in experiments.


title:
Student's t Distribution based Estimation of Distribution Algorithms for
  Derivative-free Global Optimization

abstract:
  In this paper, we are concerned with a branch of evolutionary algorithms
termed estimation of distribution (EDA), which has been successfully used to
tackle derivative-free global optimization problems. For existent EDA
algorithms, it is a common practice to use a Gaussian distribution or a mixture
of Gaussian components to represent the statistical property of available
promising solutions found so far. Observing that the Student's t distribution
has heavier and longer tails than the Gaussian, which may be beneficial for
exploring the solution space, we propose a novel EDA algorithm termed ESTDA, in
which the Student's t distribution, rather than Gaussian, is employed. To
address hard multimodal and deceptive problems, we extend ESTDA further by
substituting a single Student's t distribution with a mixture of Student's t
distributions. The resulting algorithm is named as estimation of mixture of
Student's t distribution algorithm (EMSTDA). Both ESTDA and EMSTDA are
evaluated through extensive and in-depth numerical experiments using over a
dozen of benchmark objective functions. Empirical results demonstrate that the
proposed algorithms provide remarkably better performance than their Gaussian
counterparts.


title:
Joint spectra of the tensor product representation of the direct sum of
  two solvable Lie algebras

abstract:
  Given two complex Banach spaces $X_1$ and $X_2$, a tensor product
$X_1\tilde{\otimes} X_2$ of $X_1$ and $X_2$ in the sense of [14], two complex
solvable finite dimensional Lie algebras $L_1$ and $L_2$, and two
representations $\rho_i\colon L_i\to {\rm L}(X_i)$ of the algebras, $i=1$, $2$,
we consider the Lie algebra $L=L_1\times L_2$, and the tensor product
representation of $L$, $\rho\colon L\to {\rm L}(X_1\tilde{\otimes}X_2)$,
$\rho=\rho_1\otimes I +I\otimes \rho_2$. In this work we study the
S{\l}odkowski and the split joint spectra of the representation $\rho$, and we
describe them in terms of the corresponding joint spectra of $\rho_1$ and
$\rho_2$. Moreover, we study the essential S{\l}odkowski and the essential
split joint spectra of the representation $\rho$, and we describe them by means
of the corresponding joint spectra and the corresponding essential joint
spectra of $\rho_1$ and $\rho_2$. In addition, with similar arguments we
describe all the above-mentioned joint spectra for the multiplication
representation in an operator ideal between Banach spaces in the sense of [14].
Finally, we consider nilpotent systems of operators, in particular commutative,
and we apply our descriptions to them.


title:
Accurate and Efficient Measurements of IP level Performance to Drive
  Interface Selection in Heterogeneous Wireless Networks

abstract:
  Optimal interface selection is a key mobility management issue in
heterogeneous wireless networks. Measuring the physical or link level
performance on a given wireless access networks does not provide a reliable
indication of the IP connectivity, delay and loss on the (bidirectional) paths
from the Mobile Host to the node that is handling the mobility, over different
heterogeneous networks. In this paper, we propose, implement and analyze
mechanisms for connectivity check and performance (network delay and packet
loss) monitoring over IP access networks. We evaluate the accuracy and
timeliness of the performance estimates and provide guidelines for tuning up
the parameters. From the implementation perspective, we show that using
application level measurements is highly CPU intensive, while a kernel based
implementation has comparably a very low CPU usage. The Linux kernel
implementation results in an efficient use of batteries in Mobile Hosts and
intermediate Mobility Management Nodes can scale up to monitoring thousands of
flows. The proposed solutions have been implemented in the context of a
specific mobility management solution, but the results are of general
applicability. The Linux implementation is available as Open Source.


title: Nodal curves with a contact-conic and Zariski pairs

abstract:
  In this present paper, we study the splitting of nodal plane curves with
respect to contact conics. We define the notion of splitting type of such
curves and show that it can be used as an invariant to distinguish the embedded
topology of plane curves. We also give a criterion to determine the splitting
type in terms of the configuration of the nodes and tangent points. As an
application, we construct sextics and contact conics with prescribed splitting
types, which give rise to new Zariski-triples.


title:
Enhanced charge ordering transition in doped CaFeO3 through steric
  templating

abstract:
  We report density functional theory (DFT) investigation of $B$-site doped
CaFeO$_3$, a prototypical charge-ordered perovskite. At 290 K, CaFeO$_3$
undergoes a metal-insulator transition and a charge disproportionation reaction
2Fe$^{4+}$$\rightarrow$Fe$^{5+}$+Fe$^{3+}$. We observe that when Zr dopants
occupy a (001) layer, the band gap of the resulting solid solution increases to
0.93 eV due to a 2D Jahn-Teller type distortion, where FeO$_6$ cages on the
$xy$ plane elongate along $x$ and $y$ alternatively between neighboring Fe
sites. Furthermore, we show that the rock-salt ordering of the Fe$^{5+}$ and
Fe$^{3+}$ cations can be enhanced when the $B$-site dopants are arranged in a
(111) plane due to a collective steric effect that facilitates the size
discrepancy between the Fe$^{5+}$O$_6$ and Fe$^{3+}$O$_6$ octahedra and
therefore gives rise to a larger band gap. The enhanced charge
disproportionation in these solid solutions is verified by rigorously
calculating the oxidation states of the Fe cations with different octahedral
cage sizes. We therefore predict that the corresponding transition temperature
will increase due to the enhanced charge ordering and larger band gap. The
compositional, structural and electrical relationships exploited in this paper
can be extended to a variety of perovskites and non-perovskite oxides providing
guidance in structurally manipulating electrical properties of functional
materials.


title: Classification of Metaplectic Fusion Categories

abstract:
  In this paper, we study a family of fusion and modular systems realizing
fusion categories Grothendieck equivalent to the representation category for
$so(2p+1)_2$. These categories describe non-abelian anyons dubbed `metaplectic
anyons'. We obtain explicit expressions for all the $F$- and $R$-symbols. Based
on these, we conjecture a classification for their monoidal equivalence classes
from an analysis of their gauge invariants and define a function which gives us
the number of classes.


title:
The potential role of NGC 205 in generating Andromeda's vast thin
  co-rotating plane of satellite galaxies

abstract:
  The Andromeda galaxy is observed to have a system of two large dwarf
ellipticals and ~13 smaller satellite galaxies that are currently co-rotating
in a thin plane, in addition to 2 counter-rotating satellite galaxies. We
explored the consistency of those observations with a scenario where the
majority of the co-rotating satellite galaxies originated from a subhalo group,
where NGC 205 was the host and the satellite galaxies occupied dark matter
sub-subhalos. We ran N-body simulations of a close encounter between NGC 205
and M31. In the simulations, NGC 205 was surrounded by massless particles to
statistically sample the distribution of the sub-subhalos expected in a subhalo
that has a mass similar to NGC 205. We made Monte Carlo samplings and found
that, using a set of reference parameters, the probability of producing a
thinner distribution of sub-subhalos than the observed NGC 205 + 15 smaller
satellites (thus including the 2 counter-rotators, but excluding M32) increased
from <1e-8 for the initial distribution to ~0.01 at pericentre. The probability
of the simulated sub-subhalos occupying the locations of the observed
co-rotating satellites in the line of sight velocity versus projected on-sky
distance plane is at most 0.002 for 11 out of 13 satellites. Increasing the
mass of M31 and the extent of the initial distribution of sub-subhalos gives a
maximum probability of 0.004 for all 13 co-rotating satellites, but the
probability of producing the thinness would drop to ~ 0.001.


title: Extracting Biological Pathway Models From NLP Event Representations

abstract:
  This paper describes an an open-source software system for the automatic
conversion of NLP event representations to system biology structured data
interchange formats such as SBML and BioPAX. It is part of a larger effort to
make results of the NLP community available for system biology pathway
modelers.


title: Generation of central exclusive final states

abstract:
  We present a scheme for the generation of central exclusive final states in
the Pythia 8 program. The implementation allows for the investigation of higher
order corrections to such exclusive processes as approximated by the
initial-state parton shower in Pythia 8. To achieve this, the spin and colour
decomposition of the initial-state shower has been worked out, in order to
determine the probability that a partonic state generated from an inclusive
sub-process followed by a series of initial-state parton splittings can be
considered as an approximation of an exclusive colour- and spin-singlet
process. We use our implementation to investigate effects of parton showers on
some examples of central exclusive processes, and find sizeable effects on
di-jet production, while the effects on e.g. central exclusive Higgs production
are minor.


title:
Construction of a surface integral under local Malliavin assumption and
  integration by parts formulae

abstract:
  In this paper, we consider convex sets $K_r = \{g \ge r\}$ in an infinite
dimensional Hilbert space, where $g$ is suitably related to a reference
Gaussian measure $\mu$ in $H$. We first show how to define a surface measure on
the level sets $\{g = r\}$ that is related to $\mu$. This allows to introduce
an integration-by-parts formula in $H$. This formula can be applied in several
important constructions, as for instance the case where $\mu$ is the law of a
(Gaussian) stochastic process and $H$ is the space of its trajectories


title:
Measuring the State of the Art of Automated Pathway Curation Using Graph
  Algorithms - A Case Study of the mTOR Pathway

abstract:
  This paper evaluates the difference between human pathway curation and
current NLP systems. We propose graph analysis methods for quantifying the gap
between human curated pathway maps and the output of state-of-the-art automatic
NLP systems. Evaluation is performed on the popular mTOR pathway. Based on
analyzing where current systems perform well and where they fail, we identify
possible avenues for progress.


title: Projection functions, area measures and the Alesker-Fourier transform

abstract:
  Dual to Koldobsky's notion of j-intersection bodies, the class of
j-projection bodies is introduced, generalizing Minkowski's classical notion of
projection bodies of convex bodies. A Fourier analytic characterization of
j-projection bodies in terms of their area measures of order j is obtained. In
turn, this yields an equivalent characterization of j-projection bodies
involving Alesker's Fourier type transform on translation invariant smooth
spherical valuations. As applications of these results, several basic
properties of j-projection bodies are established and new non-trivial examples
are constructed.


title:
Spatial Modeling, with Application to Complex Survey Data: Discussion of
  "Model-based Geostatistics for Prevalence Mapping in Low-Resource Settings",
  by Diggle and Giorgi

abstract:
  Prevalence mapping in low resource settings is an increasingly important
endeavor to guide policy making and to spatially and temporally characterize
the burden of disease. We will focus our discussion on consideration of the
complex design when analyzing survey data, and on spatial modeling. With
respect to the former, we consider two approaches: direct use of the weights,
and a model-based approach using a spatial model to acknowledge clustering. For
the latter we consider continuously indexed Markovian Gaussian random field
models.


title:
A Comparison of Approaches for Traffic Engineering in IP and MPLS
  Networks

abstract:
  As IP / MPLS network service providers drive for improved network
efficiencies, traffic engineering is becoming increasingly important. In this
article we review the approaches for traffic engineering in IP / MPLS networks
and present the result of a study, which compares their performance in
operational networks


title: Nominal Unification of Higher Order Expressions with Recursive Let

abstract:
  A sound and complete algorithm for nominal unification of higher-order
expressions with a recursive let is described, and shown to run in
non-deterministic polynomial time. We also explore specializations like nominal
letrec-matching for plain expressions and for DAGs and determine the complexity
of corresponding unification problems.


title:
Does Local Structure Within Shock-sheath and Magnetic Cloud Affect
  Cosmic Ray Decrease?

abstract:
  The sudden short duration decrease in cosmic ray flux is known as Forbush
decrease which is mainly caused by interplanetary disturbances. Generally
accepted view is that the first step of Forbush decrease is due to shock sheath
and second step is due to Magnetic Cloud (MC) of Interplanetary Coronal Mass
Ejection (ICME). However, there are few questions which needs detail
investigation. (i) Does the complete (or part of) ICME shock or MC contribute
in cosmic ray decrease? (ii) Is there any internal structure associated with
the ICMEs shock/MC which precisely contribute in decrease? To address these
questions we have studied a total of 18 large ($>=8 \%$) Forbush decrease
events and associated ICMEs. Majority of events shows multi-steps Forbush
decrease profile. This leads into re-classification of Forbush decrease events
depending upon the number of steps observed in their respective profile. The
present study clearly indicates that not only broad regions (shock-sheath and
MC) contribute to Forbush decrease but also localized structures within
shock-sheath and MC have very much significant importance in Forbush decrease
profile.


title:
Beyond Correlation Filters: Learning Continuous Convolution Operators
  for Visual Tracking

abstract:
  Discriminative Correlation Filters (DCF) have demonstrated excellent
performance for visual object tracking. The key to their success is the ability
to efficiently exploit available negative data by including all shifted
versions of a training sample. However, the underlying DCF formulation is
restricted to single-resolution feature maps, significantly limiting its
potential. In this paper, we go beyond the conventional DCF framework and
introduce a novel formulation for training continuous convolution filters. We
employ an implicit interpolation model to pose the learning problem in the
continuous spatial domain. Our proposed formulation enables efficient
integration of multi-resolution deep feature maps, leading to superior results
on three object tracking benchmarks: OTB-2015 (+5.1% in mean OP), Temple-Color
(+4.6% in mean OP), and VOT2015 (20% relative reduction in failure rate).
Additionally, our approach is capable of sub-pixel localization, crucial for
the task of accurate feature point tracking. We also demonstrate the
effectiveness of our learning formulation in extensive feature point tracking
experiments. Code and supplementary material are available at
http://www.cvl.isy.liu.se/research/objrec/visualtracking/conttrack/index.html.


title:
Time-varying networks approach to social dynamics: From individual to
  collective behavior

abstract:
  In this thesis we contribute to the understanding of the pivotal role of the
temporal dimension in networked social systems, previously neglected and now
uncovered by the data revolution recently blossomed in this field. To this aim,
we first introduce the time-varying networks formalism and analyze some
empirical data of social dynamics, extensively used in the rest of the thesis.
We discuss the structural and temporal properties of human contact networks,
such as heterogeneity and burstiness of social interactions, and we present a
simple model, rooted on social attractiveness, able to reproduce them. We then
explore the behavior of dynamical processes running on top of temporal
networks, constituted by empirical face-to-face interactions, addressing in
detail the fundamental cases of random walks and epidemic spreading. We also
develop an analytic approach able to compute the structural and percolation
properties of the activity driven model, aimed to describe a wide class of
social interactions, driven by the activity of the individuals involved. Our
contribution in the rapidly evolving framework of social time-varying networks
opens interesting perspectives for future work, such as the study of the impact
of the temporal dimension on multi-layered systems.


title:
High-Efficiency Device Positioning and Location-Aware Communications in
  Dense 5G Networks

abstract:
  In this article, the prospects and enabling technologies for high-efficiency
device positioning and location-aware communications in emerging 5G networks
are reviewed. We will first describe some key technical enablers and
demonstrate by means of realistic ray-tracing and map based evaluations that
positioning accuracies below one meter can be achieved by properly fusing
direction and delay related measurements on the network side, even when
tracking moving devices. We will then discuss the possibilities and
opportunities that such high-efficiency positioning capabilities can offer, not
only for location-based services in general, but also for the radio access
network itself. In particular, we will demonstrate that geometric
location-based beamforming schemes become technically feasible, which can offer
substantially reduced reference symbol overhead compared to classical full
channel state information (CSI)-based beamforming. At the same time,
substantial power savings can be realized in future wideband 5G networks where
acquiring full CSI calls for wideband reference signals while location
estimation and tracking can, in turn, be accomplished with narrowband pilots.


title: Probing the LDA-1/2 method as a starting point for $G_0W_0$ calculations

abstract:
  Employing the $G_0W_0$ approximation of Hedin's $GW$ approach one can obtain
quasi-particle energies of extended systems and molecules with good accuracy.
However, for many materials, semi-local exchange-correlation functionals are
unsatisfactory starting points for $G_0W_0$ calculations. Hybrid functionals
often improve upon them, but at a substantially higher computational cost. As
an alternative, we suggest the LDA-1/2 method, which provides reasonable band
gaps, without being computationally involved. In this work, we systematically
compare 3 starting points for $G_0W_0$: LDA, PBE0, and LDA-1/2. A selection of
solids is chosen for this benchmark: C, Si, SiC, AlP, LiF, MgO, Ne, Ar, GaN,
GaAs, CdS, ZnS, and ZnO. We demonstrate that LDA-1/2 is a good starting point
in most cases, reducing the mean absolute error of band gaps by 50% when
compared to the other 2 functionals.


title:
Determination of the thickness and orientation of few-layer tungsten
  ditelluride using polarized Raman spectroscopy

abstract:
  Orthorhombic tungsten ditelluride (WTe2), with a distorted 1T structure,
exhibits a large magnetoresistance that depends on the orientation, and its
electrical characteristics changes rom semimetallic to insulating as the
thickness decreases. Through polarized Raman spectroscopy in combination with
transmission electron diffraction, we establish a reliable method to determine
the thickness and crystallographic orientation of few-layer WTe2. The Raman
spectrum shows a pronounced dependence on the polarization of the excitation
laser. We found that the separation between two Raman peaks at ~90 cm-1 and at
80-86 cm-1, depending on thickness, is a reliable fingerprint for determination
of the thickness. For determination of the crystallographic orientation, the
polarization dependence of the A1 modes, measured with the 632.8-nm excitation,
turns out to be the most reliable. We also discovered that the polarization
behaviors of some of the Raman peaks depend on the excitation wavelength as
well as thickness, indicating a close interplay between the band structure and
anisotropic Raman scattering cross section.


title: Improved sensing with a single qubit

abstract:
  We consider quantum metrology with arbitrary prior knowledge of the
parameter. We demonstrate that a single sensing two-level system can act as a
virtual multi-level system that offers increased sensitivity in a Bayesian,
single-shot, metrology scenario and that allows one to estimate (arbitrary)
large parameter values by avoiding phase wraps. This is achieved by making use
of additional degrees of freedom or auxiliary systems not participating in the
sensing process. The joint system is manipulated by intermediate control
operations in such a way that an effective Hamiltonian, with an arbitrary
spectrum, is generated that mimics the spectrum of a multi-level system
interacting with the field. We show how to use additional internal degrees of
freedom of a single trapped ion to achieve a high-sensitivity magnetic field
sensor for fields with arbitrary prior.


title:
Branching form of the resolvent at threshold for multi-dimensional
  discrete Laplacians

abstract:
  We consider the discrete Laplacian on $\mathbb Z^d$, and compute asymptotic
expansions of its resolvent around thresholds embedded in continuous spectrum
as well as those at end points. We prove that the resolvent has a square-root
branching if $d$ is odd, and a logarithm branching if $d$ is even, and,
moreover, obtain explicit expressions for these branching parts involving the
Lauricella hypergeometric function. In order to analyze a non-degenerate
threshold of general form we use an elementary step-by-step expansion
procedure, less dependent on special functions.


title: High-throughput Ingest of Provenance Records into Accumulo

abstract:
  Whole-system data provenance provides deep insight into the processing of
data on a system, including detecting data integrity attacks. The downside to
systems that collect whole-system data provenance is the sheer volume of data
that is generated under many heavy workloads. In order to make provenance
metadata useful, it must be stored somewhere where it can be queried. This
problem becomes even more challenging when considering a network of
provenance-aware machines all collecting this metadata. In this paper, we
investigate the use of D4M and Accumulo to support high-throughput data ingest
of whole-system provenance data. We find that we are able to ingest 3,970 graph
components per second. Centrally storing the provenance metadata allows us to
build systems that can detect and respond to data integrity attacks that are
captured by the provenance system.


title: Dimesonic states with the heavy-light flavour mesons

abstract:
  In this work, we have calculated the mass spectra and decay properties of
dimesonic states in the variational scheme. The inter-mesonic interaction
considered as the Hellmann potential and One Pion Exchange potential. The mass
spectra of the $D\overline{D^{*}}$, $D^{*}\overline{D^{*}}$,
$D\overline{B^{*}}$, $B^{*}\overline{D}$, $B\overline{B^{*}}$,
$B^{*}\overline{B^{*}}$ bound states are calculated. The states X(3872),
$X_{2c}(4013)$, $Z_{b}(10610)/X_{b}$ and $Z_{b}(10650)/X_{b2}$ are compared
with $D\overline{D^{*}}$, $D^{*}\overline{D^{*}}$, $B\overline{B^{*}}$ and
$B^{*}\overline{B^{*}}$ dimesonic bound states. {\bf To probe the molecular
structure of the compared states, we have calculated the decay properties
sensitive to their long and short distance structure of the hadronic molecule.
The radiative decay for the state X(3872) into $J/\psi \gamma$ and $\psi(2S)
\gamma$ have been calculated and the ratio is found to be ten times lesser than
the experimental value whereas the other decay modes are comparable with other
theoretical and experimental results. This results restrict us to assigned the
pure molecular structure to the X(3872). But, Our results suggests that the
compared states are close to the molecular structure or have dominant molecular
component in their wave function. Apart from these, the other calculated mass
spectra of dimesonic states are predicted and for such bound states, the
experimental search are suggested.}


title: Wavelet transforms for homogeneous mixed-norm Triebel--Lizorkin spaces

abstract:
  Homogeneous mixed-norm Triebel--Lizorkin spaces are introduced and studied
with the use of a discrete wavelet transformation, the so-called
$\varphi$-transform. This extends the classical $\varphi$-transform approach
introduced by Frazier and Jawerth to the setting of mixed-norm spaces.
Moreover, the theory of the $\varphi$-transform is enhanced through a precise
definition of the synthesis operator, in terms of a Pettis integral, and a
number of rigorous results for this operator. Especially its terms can always
be summed in any order, without changing the resulting distribution.


title: Weyl semimetals as catalysts

abstract:
  The search for highly efficient and low-cost catalysts is one of the main
driving forces in catalytic chemistry. Current strategies for the catalyst
design focus on increasing the number and activity of local catalytic sites,
such as the edge-sites of molybdenum disulfides in the hydrogen evolution
reaction (HER). Here, we propose and demonstrate a different principle that
goes beyond local site optimization by utilizing topological electronic states,
a global property of the material, to spur catalytic activity. For HER, we have
found excellent catalysts among the transition-metal monopnictides - NbP, TaP,
NbAs, and TaAs - which were recently discovered to be topological Weyl
semimetals. In addition to the free energy considerations we explore the role
of metallicity, carrier mobility and topological electronic states for
remarkable HER performance of these materials. The combination of robust
topological surface states and large room temperature carrier mobility both of
which originate from bulk Dirac bands of the Weyl semimetal appears to be the
recipe for good HER catalyst. Our work provides a guiding principle for the
discovery of novel catalysts from the emerging field of topological materials.


title:
Cameron-Martin theorems for sequences of symmetric Cauchy-distributed
  random variables

abstract:
  Given a sequence of Cauchy-distributed random variables defined by a sequence
of location parameters and a sequence of scale parameters, we consider another
sequence of random variables that is obtained by perturbing the location or
scale parameter sequences. Using a result of Kakutani on equivalence of
infinite product measures, we provide sufficient conditions for the equivalence
of laws of the two sequences.


title: Compositional Distributional Cognition

abstract:
  We accommodate the Integrated Connectionist/Symbolic Architecture (ICS) of
[32] within the categorical compositional semantics (CatCo) of [13], forming a
model of categorical compositional cognition (CatCog). This resolves intrinsic
problems with ICS such as the fact that representations inhabit an unbounded
space and that sentences with differing tree structures cannot be directly
compared. We do so in a way that makes the most of the grammatical structure
available, in contrast to strategies like circular convolution. Using the CatCo
model also allows us to make use of tools developed for CatCo such as the
representation of ambiguity and logical reasoning via density matrices,
structural meanings for words such as relative pronouns, and addressing over-
and under-extension, all of which are present in cognitive processes. Moreover
the CatCog framework is sufficiently flexible to allow for entirely different
representations of meaning, such as conceptual spaces. Interestingly, since the
CatCo model was largely inspired by categorical quantum mechanics, so is
CatCog.


title: On Deformations of Hyperbolic Varities

abstract:
  In this paper we study flat deformations of real subschemes of
$\mathbb{P}^n$, hyperbolic with respect to a fixed linear subspace, i.e.
admitting a finite surjective and real fibered linear projection. We show that
the subset of the corresponding Hilbert scheme consisting of such subschemes is
closed and connected in the classical topology. Every smooth variety in this
set lies in the interior of this set. Furthermore, we provide sufficient
conditions for a hyperbolic subscheme to admit a flat deformation to a smooth
hyperbolic subscheme. This leads to new examples of smooth hyperbolic
varieties.


title: Non-stationary Gaussian models with physical barriers

abstract:
  The classical tools in spatial statistics are stationary models, like the
Mat\'ern field. However, in some applications there are boundaries, holes, or
physical barriers in the study area, e.g. a coastline, and stationary models
will inappropriately smooth over these features, requiring the use of a
non-stationary model.
  We propose a new model, the Barrier model, which is different from the
established methods as it is not based on the shortest distance around the
physical barrier, nor on boundary conditions. The Barrier model is based on
viewing the Mat\'ern correlation, not as a correlation function on the shortest
distance between two points, but as a collection of paths through a
Simultaneous Autoregressive (SAR) model. We then manipulate these local
dependencies to cut off paths that are crossing the physical barriers. To make
the new SAR well behaved, we formulate it as a stochastic partial differential
equation (SPDE) that can be discretised to represent the Gaussian field, with a
sparse precision matrix that is automatically positive definite.
  The main advantage with the Barrier model is that the computational cost is
the same as for the stationary model. The model is easy to use, and can deal
with both sparse data and very complex barriers, as shown in an application in
the Finnish Archipelago Sea. Additionally, the Barrier model is better at
reconstructing the modified Horseshoe test function than the standard models
used in R-INLA.


title: The chemical compositions of solar twins in the open cluster M67

abstract:
  Stars in open clusters are expected to share an identical abundance pattern.
Establishing the level of chemical homogeneity in a given open cluster deserves
further study as it is the basis of the concept of chemical tagging to unravel
the history of the Milky Way. M67 is particularly interesting given its solar
metallicity and age as well as being a dense cluster environment. We conducted
a strictly line-by-line differential chemical abundance analysis of two solar
twins in M67: M67-1194 and M67-1315. Stellar atmospheric parameters and
elemental abundances were obtained with high precision using Keck/HIRES
spectra. M67-1194 is essentially identical to the Sun in terms of its stellar
parameters. M67-1315 is warmer than M67-1194 by ~ 150 K as well as slightly
more metal-poor than M67-1194 by ~ 0.05 dex. M67-1194 is also found to have
identical chemical composition to the Sun, confirming its solar twin nature.
The abundance ratios [X/Fe] of M67-1315 are similar to the solar abundances for
elements with atomic number Z <= 30, while most neutron-capture elements are
enriched by ~ 0.05 dex, which might be attributed to enrichment from a mixture
of AGB ejecta and r-process material. The distinct chemical abundances for the
neutron-capture elements in M67-1315 and the lower metallicity of this star
compared to M67-1194, indicate that the stars in M67 are likely not chemically
homogeneous. This poses a challenge for the concept of chemical tagging since
it is based on the assumption of stars forming in the same star-forming
aggregate.


title:
Thermal non-equilibriuem revealed by periodic pulses of random
  amplitudes in solar coronal loops

abstract:
  We recently detected variations in extreme ultraviolet intensity in coronal
loops repeating with periods of several hours. Models of loops including
stratified and quasi-steady heating predict the development of a state of
thermal non-equilibrium (TNE): cycles of evaporative upflows at the footpoints
followed by falling condensations at the apex. Based on Fourier and wavelet
analysis, we demonstrate that the observed periodic signals are indeed not
signatures of vibrational modes. Instead, superimposed on the power law
expected from the stochastic background emission, the power spectra of the time
series exhibit the discrete harmonics and continua expected from periodic
trains of pulses of random amplitudes. These characteristics reinforce our
earlier interpretation of these pulsations as being aborted TNE cycles.


title: On ZRP wind input term consistency in Hasselmann equation

abstract:
  The new ZRP wind input source term (Zakharov et al. 2012) is checked for its
consistency via numerical simulation of Hasselmann equation. The results are
compared to field experimental data, collected at different sites around the
world, and theoretical predictions of self-similarity analysis. Good agreement
is obtained for limited fetch and time domain statements


title:
Room-temperature synthesis of graphene-like carbon sheets from C2H2, CO2
  and CO on copper foils

abstract:
  A high temperature for some catalytic reactions like synthesis of large area
and high quality graphene is required. The mentioned graphene can be obtained
by a chemical vapour deposition (CVD) process on copper foil at 800 1000. Here,
we describe a room temperature synthesis method from different carbon sources
for the first time, including acetylene, carbon dioxide and carbon monoxide, on
copper foil by using a heuristic method which was inspired from the role of
some electronic promoters in catalyst science. Promoters are substances that
increase the catalytic activity, but they are not catalysts by themselves. In
this study, we used charges to modify the electronic effects of the catalysts,
which were produced by piezoelectric materials.


title: The small-scale HH34 IRS jet as seen by X-shooter

abstract:
  Very little information has been so far gathered on atomic jets from young
embedded low mass sources (class I stars), especially in the inner jet region.
We exploit multiwave spectroscopic observations to infer physical conditions of
the inner region of HH34 IRS, a prototypical class I jet. We use a deep
X-shooter spectrum ( lambda = 350-2300 nm, R between 8000 and 18000) detecting
lines with upper energies from 8000 to 31000 cm-1 . Statistical equilibrium and
ionization models are adopted to derive the jet main physical parameters. We
derive the physical conditions for the extended high velocity jet (HVC, V about
-100 km/s) and for the low velocity and compact gas (LVC, V about -20-50 \kms).
At the jet base (< 200 AU) the HVC is mostly neutral (x(e)< 0.1) and very dense
(n(H) > 5x10^5 cm-3). The LVC gas has the same density and A_V as the HVC, but
it is a factor of two colder. Iron abundance in the HVC is close to solar,
while it is 3 times subsolar in the LVC, suggesting an origin of the LVC gas
from a dusty disk. We infer a jet mass flux rate > 5x10^{-7} Mo/yr. We find
that the relationships between accretion luminosity and line luminosity derived
for T Tauri stars cannot be directly extended to class I sources surrounded by
reflection nebulae since the permitted lines are seen through scattered light.
An accretion rate of about 7\,10^{-6} Mo/yr is instead derived from an
empirical relationship connecting the mass accretion rate with L([OI])(HVC). In
conclusion, the HH34 IRS jet shares many properties with jets from active CTTs
stars. It is however denser as a consequence of the larger mass flux rate.
These findings suggest that the acceleration and excitation mechanisms in jets
are not influenced by evolution and are similar in CTTs and in still embedded
and highly accreting sources.


title: Applying Deep Learning to Basketball Trajectories

abstract:
  One of the emerging trends for sports analytics is the growing use of player
and ball tracking data. A parallel development is deep learning predictive
approaches that use vast quantities of data with less reliance on feature
engineering. This paper applies recurrent neural networks in the form of
sequence modeling to predict whether a three-point shot is successful. The
models are capable of learning the trajectory of a basketball without any
knowledge of physics. For comparison, a baseline static machine learning model
with a full set of features, such as angle and velocity, in addition to the
positional data is also tested. Using a dataset of over 20,000 three pointers
from NBA SportVu data, the models based simply on sequential positional data
outperform a static feature rich machine learning model in predicting whether a
three-point shot is successful. This suggests deep learning models may offer an
improvement to traditional feature based machine learning methods for tracking
data.


title:
On the theory of solitons of fluid pressure and solute density in
  geologic porous media, with applications to shale, clay and sandstone

abstract:
  In this paper we propose the application of a new model of transients of pore
pressure p and solute density \r{ho} in geologic porous media. This model is
rooted in the non-linear waves theory, the focus of which is advection and
effect of large pressure jumps on strain (due to large p in a non-linear
version of the Hooke law). It strictly relates p and \r{ho} evolving under the
effect of a strong external stress. As a result, the presence of quick and
sharp transients in low permeability rocks is unveiled, i.e. the non-linear
Burgers solitons. We therefore propose that the actual transport process in
porous rocks for large signals is not the linear diffusion, but could be
governed by solitons. A test of an eventual presence of solitons in a rock is
here proposed, and then applied to Pierre Shale, Bearpaw Shale, Boom Clay and
Oznam-Mugu silt and clay. A quick analysis showing the presence of solitons for
nuclear waste disposal and salty water intrusions is also analyzed. Finally, in
a kind of "theoretical experiment" we show that solitons could also be present
in Jordan and St. Peter sandstones, thus suggesting the occurrence of osmosis
in these rocks.


title: The algebraic chromatic splitting conjecture for Noetherian ring spectra

abstract:
  We formulate a version of Hopkins' chromatic splitting conjecture for an
arbitrary structured ring spectrum $R$, and prove it whenever $\pi_*R$ is
Noetherian. As an application, these results provide a new local-to-global
principle in the modular representation theory of finite groups.


title: Around $\ell$-independence

abstract:
  In this article we study various forms of $\ell$-independence (including the
case $\ell=p$) for the cohomology and fundamental groups of varieties over
finite fields and equicharacteristic local fields. Our first result is a strong
form of $\ell$-independence for the unipotent fundamental group of smooth and
projective varieties over finite fields, by then proving a certain `spreading
out' result we are able to deduce a much weaker form of $\ell$-independence for
unipotent fundamental groups over equicharacteristic local fields, at least in
the semistable case. In a similar vein, we can also use this to deduce
$\ell$-independence results for the cohomology of semistable varieties from the
well-known results on $\ell$-independence for smooth and proper varieties over
finite fields. As another consequence of this `spreading out' result we are
able to deduce the existence of a Clemens--Schmid exact sequence for formal
semistable families. Finally, by deforming to characteristic $p$ we show a
similar weak version of $\ell$-independence for the unipotent fundamental group
of a semistable curve in mixed characteristic.


title: Resurgence of the dressing phase for ${\rm AdS}_5\times {\rm S}^5$

abstract:
  We discuss the resummation of the strong coupling asymptotic expansion of the
dressing phase of the ${\rm AdS}_5\times {\rm S}^5$ superstring. The dressing
phase proposed by Beisert, Eden and Staudacher can be recovered from a modified
Borel-Ecalle resummation of this asymptotic expansion only by completing it
with new, non-perturbative and exponentially suppressed terms that can be
organized into different sectors labelled by an instanton-like number. We
compute the contribution to the dressing phase coming from the sum over all the
instanton sectors and show that it satisfies the homogeneous crossing symmetry
equation. We comment on the semiclassical origin of the non-perturbative terms
from the world-sheet theory point of view even though their precise explanation
remains still quite mysterious.


title:
Exponential convergence under distributed averaging integral frequency
  control

abstract:
  We investigate the performance and robustness of distributed averaging
integral controllers used in the optimal frequency regulation of power
networks. We construct a strict Lyapunov function that allows us to quantify
the exponential convergence rate of the closed-loop system. As an application,
we study the stability of the system in the presence of disruptions to the
controllers' communication network, and investigate how the convergence rate is
affected by these disruptions.


title:
Formation of the Unequal-Mass Binary Protostars in L1551 NE by
  Rotationally-Driven Fragmentation

abstract:
  We present observations at 7 mm that fully resolve the two circumstellar
disks, and a reanalyses of archival observations at 3.5 cm that resolve along
their major axes the two ionized jets, of the class I binary protostellar
system L1551 NE. We show that the two circumstellar disks are better fit by a
shallow inner and steep outer power-law than a truncated power-law. The two
disks have very different transition radii between their inner and outer
regions of $\sim$18.6 AU and $\sim$8.9 AU respectively. Assuming that they are
intrinsically circular and geometrically thin, we find that the two
circumstellar disks are parallel with each other and orthogonal in projection
to their respective ionized jets. Furthermore, the two disks are closely
aligned if not parallel with their circumbinary disk. Over an interval of
$\sim$10 yr, source B (possessing the circumsecondary disk) has moved
northwards with respect to and likely away from source A, indicating an orbital
motion in the same direction as the rotational motion of their circumbinary
disk. All the aforementioned elements therefore share the same axis for their
angular momentum, indicating that L1551 NE is a product of rotationally-driven
fragmentation of its parental core. Assuming a circular orbit, the relative
disk sizes are compatible with theoretical predictions for tidal truncation by
a binary system having a mass ratio of $\sim$0.2, in agreement with the
reported relative separations of the two protostars from the center of their
circumbinary disk. The transition radii of both disks, however, are a factor of
$\gtrsim$1.5 smaller than their predicted tidally-truncated radii.


title:
The effect of interplanetary magnetic field orientation on the solar
  wind flux impacting Mercury's surface

abstract:
  The aim of this paper is to study the plasma flows on the Mercury surface for
different interplanetary magnetic field orientations on the day side of the
planet. We use a single fluid MHD model in spherical coordinates to simulate
the interaction of the solar wind with the Hermean magnetosphere for six solar
wind realistic configurations with different magnetic field orientations:
Mercury-Sun, Sun-Mercury, aligned with the magnetic axis of Mercury (Northward
and Southward) and with the orbital plane perpendicular to the previous cases.
In the Mercury-Sun (Sun-Mercury) simulation the Hermean magnetic field is
weakened in the South-East (North-East) of the magnetosphere leading to an
enhancement of the flows on the South (North) hemisphere. For a Northward
(Southward) orientation there is an enhancement (weakening) of the Hermean
magnetic field in the nose of the bow shock so the fluxes are reduced and
drifted to the poles (enhanced and drifted to the equator). If the solar wind
magnetic field is in the orbital plane the magnetosphere is tilted to the West
(East) and weakened at the nose of the shock, so the flows are enhanced and
drifted to the East (West) in the Northern hemisphere and to the West (East) in
the Southern hemisphere.


title:
Electron Bunch Train Excited Higher-Order Modes in a Superconducting RF
  Cavity

abstract:
  Higher-order mode (HOM) based intra-cavity beam diagnostics has been proved
effectively and conveniently in superconducting radio-frequency (SRF)
accelerators. Our recent research shows that the beam harmonics in the bunch
train excited HOM spectrum, which have much higher signal-to-noise ratio than
the intrinsic HOM peaks, may also be useful for beam diagnostics. In this
paper, we will present our study on bunch train excited HOMs, including the
theoretic model and recent experiments carried out based on the DC-SRF
photoinjector and SRF linac at Peking University.


title:
Density vs distance for the DUNE beam from two recent geology density
  maps

abstract:
  The densities passed through for neutrinos going from Fermilab to Sanford lab
are obtained using two recent density tables, crustal [1] and
Shen-Ritzwoller[2], as well as the values from an older table PEMC[3].


title: Redefining part-of-speech classes with distributional semantic models

abstract:
  This paper studies how word embeddings trained on the British National Corpus
interact with part of speech boundaries. Our work targets the Universal PoS tag
set, which is currently actively being used for annotation of a range of
languages. We experiment with training classifiers for predicting PoS tags for
words based on their embeddings. The results show that the information about
PoS affiliation contained in the distributional vectors allows us to discover
groups of words with distributional patterns that differ from other words of
the same part of speech.
  This data often reveals hidden inconsistencies of the annotation process or
guidelines. At the same time, it supports the notion of `soft' or `graded' part
of speech affiliations. Finally, we show that information about PoS is
distributed among dozens of vector components, not limited to only one or two
features.


title: The uniqueness of $PSU_3(8)$ in the Monster

abstract:
  As a contribution to an eventual solution of the problem of determination of
the maximal subgroups of the Monster we show that there is a unique conjugacy
class of subgroups isomorphic to $PSU_3(8)$. The argument depends on some
computations in various subgroups, but not on computations in the Monster
itself.


title: Theory of electric dipole moments and lepton flavour violation

abstract:
  Electric dipole moments and charged-lepton flavour-violating processes are
extremely sensitive probes for new physics, complementary to direct searches as
well as flavour-changing processes in the quark sector. Beyond the
"smoking-gun" feature of a potential significant measurement, however, it is
crucial to understand their implications for new physics models quantitatively.
The corresponding multi-scale problem of relating the existing high-precision
measurements to fundamental parameters can be approached model-independently to
a large extent; however, care must be taken to include the uncertainties from
especially nuclear and QCD calculations properly.


title:
Versatile method for renormalized stress-energy computation in
  black-hole spacetimes

abstract:
  We report here on a new method for calculating the renormalized stress-energy
tensor (RSET) in black-hole (BH) spacetimes, which should also be applicable to
dynamical BHs and to spinning BHs. This new method only requires the spacetime
to admit a single symmetry. So far we developed three variants of the method,
aimed for stationary, spherically symmetric, or axially symmetric BHs. We used
this method to calculate the RSET of a minimally-coupled massless scalar field
in Schwarzschild and Reissner-Nordstrom backgrounds, for several quantum
states. We present here the results for the RSET in the Schwarzschild case in
Unruh state (the state describing BH evaporation). The RSET is type I at weak
field, and becomes type IV at $r\lesssim2.78M$. Then we use the RSET results to
explore violation of the weak and null Energy conditions. We find that both
conditions are violated all the way from $r\simeq4.9M$ to the horizon. We also
find that the averaged weak energy condition is violated by a class of
(unstable) circular timelike geodesics. Most remarkably, the circular null
geodesic at $r=3M$ violates the averaged null energy condition.


title: The Cartan Model for Equivariant Cohomology

abstract:
  In this article, we will discuss a new operator $d_{C}$ on
$W(\mathfrak{g})\otimes\Omega^{*}(M)$ and to construct a new Cartan model for
equivariant cohomology. We use the new Cartan model to construct the
corresponding BRST model and Weil model, and discuss the relations between
them.


title:
Manifestations of the rotation and gravity of the Earth in high-energy
  physics experiments

abstract:
  The inertial (due to rotation) and gravitational fields of the Earth affect
the motion of an elementary particle and its spin dynamics. This influence is
not negligible and should be taken into account in high-energy physics
experiments. Earth's influence is manifest in perturbations in the particle
motion, in an additional precession of the spin, and in a change of the
constitutive tensor of the Maxwell electrodynamics. Bigger corrections are
oscillatory, and their contributions average to zero. Other corrections due to
the inhomogeneity of the inertial field are not oscillatory but they are very
small and may be important only for the storage ring electric dipole moment
experiments. Earth's gravity causes the Newton-like force, the reaction force
provided by a focusing system, and additional torques acting on the spin.
However, there are no observable indications of the electromagnetic effects due
to Earth's gravity.


title:
On the Diophantine equation $f(x)f(y)=f(z)^n$ involving Laurent
  polynomials

abstract:
  By the theory of elliptic curves, we investigate the nontrivial rational
parametric solutions of the Diophantine equation $f(x)f(y)=f(z)^n$, where
$n=1,2$ and $f(X)$ are some simple Laurent polynomials.


title:
On the Diophantine equations $z^2=f(x)^2 \pm f(y)^2$ involving Laurent
  polynomials

abstract:
  By the theory of elliptic curves, we study the nontrivial rational parametric
solutions and rational solutions of the Diophantine equations $z^2=f(x)^2 \pm
f(y)^2$ for some simple Laurent polynomials $f$.


title: Content-based image retrieval tutorial

abstract:
  This paper functions as a tutorial for individuals interested to enter the
field of information retrieval but wouldn't know where to begin from. It
describes two fundamental yet efficient image retrieval techniques, the first
being k - nearest neighbors (knn) and the second support vector machines(svm).
The goal is to provide the reader with both the theoretical and practical
aspects in order to acquire a better understanding. Along with this tutorial we
have also developed the equivalent software1 using the MATLAB environment in
order to illustrate the techniques, so that the reader can have a hands-on
experience.


title: Modeling Kleinian cosmology with electronic metamaterials

abstract:
  This paper deals with the propagation of Klein-Gordon particles in flat
background spacetime exhibiting discontinuous metric changes from a Lorentzian
signature (-,+,+,+) to a Kleinian signature (-,+,+,-). A formal analogy with
the propagation of electrons at a junction between an anisotropic semiconductor
and an electronic metamaterial is presented. From that analogy, we study the
dynamics of these particles falling onto planar boundary interfaces between
these two families of media and show a mirror-like behavior for the particle
flux. Finally, the case of a double junction of finite thickness is examined
and the possibility of tunneling through it is discussed. A physical link
between the metamaterial and the Kleinian slabs is found by calculating the
time of flight of the respective traversing particles.


title:
Effective perihelion advance and potentials in a conformastatic
  background with magnetic field

abstract:
  An Exact solution of the Einstein-Maxwell field equations for a
conformastatic metric with magnetized sources is study. In this context,
effective potential are studied in order to understand the dynamics of the
magnetic field in galaxies. We derive the equations of motion for neutral and
charged particles in a spacetime background characterized by this class of
solutions. In this particular case, we investigate the main physical properties
of equatorial circular orbits and related effective potentials. In addition, we
obtain an effective analytic expression for the perihelion advance of test
particles. Our theoretical predictions are compared with the observational data
calibrated with the ephemerides of the planets of the Solar system and the Moon
(EPM2011). We show that, in general, the magnetic punctual mass predicts values
that are in better agreement with observations than the values predicted in
Einstein gravity alone.


title: Higher-Order Functions and Brouwer's Thesis

abstract:
  Extending Mart\'in Escard\'o's effectful forcing technique, we give a new
proof of a well-known result: Brouwer's monotone bar theorem holds for any bar
that can be realized by a functional of type $(\mathbb{N} \to \mathbb{N}) \to
\mathbb{N}$ in G\"odel's System T. Effectful forcing is an elementary
alternative to standard sheaf-theoretic forcing arguments, using ideas from
programming languages, including computational effects, monads, the algebra
interpretation of call-by-name ${\lambda}$-calculus, and logical relations. Our
argument proceeds by interpreting System T programs as well-founded dialogue
trees whose nodes branch on a query to an oracle of type
$\mathbb{N}\to\mathbb{N}$, lifted to higher type along a call-by-name
translation. To connect this interpretation to the bar theorem, we then show
that Brouwer's famous "mental constructions" of barhood constitute an invariant
form of these dialogue trees in which queries to the oracle are made maximally
and in order.


title: Optimal quantizers for some absolutely continuous probability measures

abstract:
  The representation of a given quantity with less information is often
referred to as `quantization' and it is an important subject in information
theory. In this paper, we have considered absolutely continuous probability
measures on unit discs, squares, and the real line. For these probability
measures the optimal sets of $n$-means and the $n$th quantization errors are
calculated for some positive integers $n$.


title: BFKL pomeron with massive gluons and running coupling

abstract:
  In this paper we proceed with the study of the Pomeron spectrum, by solving
numerically the BFKL equation with massive gluons and running coupling. The
spectrum of Regge singularities is discrete and the leading Pomeron has a
considerable dependence on nonperturbative effects, for which we use Higgs
mechanism as a model. We cross-checked this result with variational method and
confirmed the infrared sensitivity of leading Pomeron. This fact is related to
the infrared instability of the BFKL equation in QCD, with a running coupling.
The subleading poles have a mild sensitivity to the soft physics, and are well
described by known semiclassical methods. We also discuss the dependence on
various prescriptions of the running coupling arguments.


title:
Scaling Factorial Hidden Markov Models: Stochastic Variational Inference
  without Messages

abstract:
  Factorial Hidden Markov Models (FHMMs) are powerful models for sequential
data but they do not scale well with long sequences. We propose a scalable
inference and learning algorithm for FHMMs that draws on ideas from the
stochastic variational inference, neural network and copula literatures. Unlike
existing approaches, the proposed algorithm requires no message passing
procedure among latent variables and can be distributed to a network of
computers to speed up learning. Our experiments corroborate that the proposed
algorithm does not introduce further approximation bias compared to the proven
structured mean-field algorithm, and achieves better performance with long
sequences and large FHMMs.


title:
Super-convergence and post-processing for mixed finite element
  approximations of the wave equation

abstract:
  We consider the numerical approximation of acoustic wave propagation problems
by mixed BDM(k+1)-P(k) finite elements on unstructured meshes. Optimal
convergence of the discrete velocity and super-convergence of the pressure by
one order are established. Based on these results, we propose a post-processing
strategy that allows us to construct an improved pressure approximation from
the numerical solution. Corresponding results are well-known for mixed finite
element approximations of elliptic problems and we extend these analyses here
to the hyperbolic problem under consideration. We also consider the subsequent
time discretization by the Crank-Nicolson method and show that the analysis and
the post-processing strategy can be generalized to the fully discrete schemes.
Our proofs do not rely on duality arguments or inverse inequalities and the
results therefore apply also for non-convex domains and non-uniform meshes.


title: DeepDiary: Automatic Caption Generation for Lifelogging Image Streams

abstract:
  Lifelogging cameras capture everyday life from a first-person perspective,
but generate so much data that it is hard for users to browse and organize
their image collections effectively. In this paper, we propose to use automatic
image captioning algorithms to generate textual representations of these
collections. We develop and explore novel techniques based on deep learning to
generate captions for both individual images and image streams, using temporal
consistency constraints to create summaries that are both more compact and less
noisy. We evaluate our techniques with quantitative and qualitative results,
and apply captioning to an image retrieval application for finding potentially
private images. Our results suggest that our automatic captioning algorithms,
while imperfect, may work well enough to help users manage lifelogging photo
collections.


title:
Recursive cheating strategies for the relativistic $F_Q$ bit commitment
  protocol

abstract:
  In this paper, we study relativistic bit commitment, which uses timing and
location constraints to achieve information theoretic security. We consider the
$F_Q$ multi-round bit commitment scheme introduced by Lunghi et al. [LKB+15].
This protocol was shown secure against classical adversaries as long as the
number of rounds $m$ is small compared to $\sqrt{Q}$ where $Q$ is the size of
the used field in the protocol [CCL15,FF16].
  In this work, we study classical attacks on this scheme. We use classical
strategies for the $CHSH_Q$ game described in [BS15] to derive cheating
strategies for this protocol. In particular, our cheating strategy shows that
if $Q$ is an even power of any prime, then the protocol is not secure when the
number of rounds $m$ is of the order of $\sqrt{Q}$. For those values of $Q$,
this means that the upper bound of [CCL15,FF16] is essentially optimal.


title:
A revisited Johnson-Mehl-Avrami-Kolmogorov model and the evolution of
  grain-size distributions in steel

abstract:
  The classical Johnson-Mehl-Avrami-Kolmogorov approach for nucleation and
growth models of diffusive phase transitions is revisited and applied to model
the growth of ferrite in multiphase steels. For the prediction of mechanical
properties of such steels, a deeper knowledge of the grain structure is
essential. To this end, a Fokker-Planck evolution law for the volume
distribution of ferrite grains is developed and shown to exhibit a log-normally
distributed solution. Numerical parameter studies are given and confirm
expected properties qualitatively. As a preparation for future work on
parameter identification, a strategy is presented for the comparison of volume
distributions with area distributions experimentally gained from polished
micrograph sections.


title:
Study of extreme states of matter at high energy densities and high
  strain rates with powerful lasers

abstract:
  In the paper, a review of most important results of experimental studies of
thermonuclear plasma in conical targets, generation of shock waves and
spallation phenomena in different materials, which were carried out at laser
facilities of the A M Prokhorov General Physics Institute RAS since 1977, is
presented.


title: Minimal contact triangulations of 3-manifolds

abstract:
  In this paper, we explore minimal contact triangulations on contact
3-manifolds. We give many explicit examples of contact triangulations that are
close to minimal ones. The main results of this article say that on any closed
oriented 3-manifold the number of vertices for minimal contact triangulations
for overtwisted contact structures grows at most linearly with respect to the
relative $d^3$ invariant. We conjecture that this bound is optimal. We also
discuss, in great details, contact triangulations for a certain family of
overtwisted contact structures on 3-torus.


title: Perceptual Reward Functions

abstract:
  Reinforcement learning problems are often described through rewards that
indicate if an agent has completed some task. This specification can yield
desirable behavior, however many problems are difficult to specify in this
manner, as one often needs to know the proper configuration for the agent. When
humans are learning to solve tasks, we often learn from visual instructions
composed of images or videos. Such representations motivate our development of
Perceptual Reward Functions, which provide a mechanism for creating visual task
descriptions. We show that this approach allows an agent to learn from rewards
that are based on raw pixels rather than internal parameters.


title:
Coded Network Function Virtualization: Fault Tolerance via In-Network
  Coding

abstract:
  Network Function Virtualization (NFV) prescribes the instantiation of network
functions on general-purpose network devices, such as servers and switches.
While yielding a more flexible and cost-effective network architecture, NFV is
potentially limited by the fact that commercial off-the-shelf hardware is less
reliable than the dedicated network elements used in conventional cellular
deployments. The typical solution for this problem is to duplicate network
functions across geographically distributed hardware in order to ensure
diversity. In contrast, this letter proposes to leverage channel coding in
order to enhance the robustness on NFV to hardware failure. The proposed
approach targets the network function of uplink channel decoding, and builds on
the algebraic structure of the encoded data frames in order to perform
in-network coding on the signals to be processed at different servers. The key
principles underlying the proposed coded NFV approach are presented for a
simple embodiment and extensions are discussed. Numerical results demonstrate
the potential gains obtained with the proposed scheme as compared to the
conventional diversity-based fault-tolerant scheme in terms of error
probability.


title:
Effect of interfacial intermixing on the Dzyaloshinskii-Moriya
  interaction in Pt/Co/Pt

abstract:
  We study the effect of sputter-deposition conditions, namely substrate
temperature and chamber base pressure, upon the interface quality of epitaxial
Pt/Co/Pt thin films with perpendicular magnetic anisotropy. Here we define
interface quality to be the inverse of the sum in quadrature of roughness and
intermixing. We find that samples with the top Co/Pt layers grown at 250
degrees C exhibit a local maximum in roughness-intermixing and that the
interface quality is better for lower or higher deposition temperatures, up to
400 degrees C, above which the interface quality degrades. Imaging the
expansion of magnetic domains in an in-plane field using wide-field Kerr
microscopy, we determine the interfacial Dzyaloshinskii-Moriya interaction
(DMI) in films in the deposition temperature range 100 degrees C to 300 degrees
C. The net DMI is linked to the difference in top and bottom Co interface
qualities; the net DMI increases as the difference between top and bottom Co
interface quality increases. Furthermore, for sufficiently low base pressures,
the net DMI increases linearly with the deposition temperature, indicating that
fine-tuning of the DMI may be achieved via the deposition conditions.


title:
Evidence for a two-fold symmetric superconducting gap in a monolayer of
  FeSe$_{0.5}$Te$_{0.5}$ on a topological insulator

abstract:
  We present our investigations on the superconducting properties of monolayers
of FeSe$_{0.5}$Te$_{0.5}$ grown on the 3D topological insulator
Bi$_{2}$Se$_{1.2}$Te$_{1.8}$ using low temperature scanning tunneling
spectroscopy (STS). While the morphology and the overall transition temperature
resemble those of similarly doped bulk crystals, the spatially resolved
spectroscopic data at 1.1K shows a much larger spatial inhomogeneity in the
superconducting energy gaps. Despite the gap inhomogeneity all the spectra can
be fitted with a two-fold anisotropic s-wave gap function. The two-fold nature
of the gap symmetry is evident from the Bogoliubov quasiparticle interference
(QPI) pattern which shows distinct C$_{2}$ symmetric scattering intensities. We
argue that the gap inhomogeneity emerges as a result of intrinsic disorder in
our system similar to disordered conventional superconductors. Even though most
of our findings clearly differ from the current understanding of the
corresponding bulk system, it provides an ideal platform to study
unconventional superconductivity in Fe chalcogenides thinned down to a single
layer and in close proximity to a topological insulator.


title:
Prutor: A System for Tutoring CS1 and Collecting Student Programs for
  Analysis

abstract:
  An introductory programming course (CS1) is an integral part of any
undergraduate curriculum. Due to large number and diverse programming
background of students, providing timely and personalised feedback to
individual students is a challenging task for any CS1 instructor. The help
provided by teaching assistants (typically senior students) is not sufficient
as it suffers from unintentional bias and, most of the time, not quick enough.
  In this paper, we present Prutor, a tutoring system platform to conduct
introductory programming courses. Prutor is a cloud-based web application that
provides instant and useful feedback to students while solving programming
problems. Prutor stores, at regular intervals, the snapshots of students'
attempts to solve programming problems. These intermediate versions of the
student programs provide the instructors (and data analysts) a view of the
students' approach to solving programming problems. Since Prutor is accessible
through any standard web browser, students do not need to worry about
dependencies external to the programming course, viz. Operating Systems,
Editors, Compilers, Compiler Options, etc.. This enables the students to focus
on solving only the programming problems. Apart from the code snapshots at
regular intervals, Prutor also collects other valuable data such as the time
taken by the students to solve the problems, the number of compile and
execution events, and the errors made. We have used this data in developing
intelligent tools for giving feedback to students, some of which are described
briefly in this paper. This system thus serves as a platform for tutoring as
well as data collection for researchers.


title: Remarks on $\phi$-coordinated modules for quantum vertex algebras

abstract:
  This paper is about $\phi$-coordinated modules for weak quantum vertex
algebras. Among the main results, several canonical connections among
$\phi$-coordinated modules for different $\phi$ are established. For vertex
operator algebras, a reinterpretation of Frenkel-Huang-Lepowsky's theorem on
contragredient module is given in terms of $\phi$-coordinated modules.


title: Gravito-magnetic monopoles in traversable wormholes from WIMT

abstract:
  Using Weitzenb\"ock Induced Matter Theory (WIMT), we study Schwarzschild
wormholes performing different foliations on an extended (non-vaccuum) 5D
manifold. We explore the geodesic equations for observers which are in the
interior of a traversable wormhole and how these observers can detect
gravito-magnetic monopoles which are dual to gravito-electric sources observed
in the outer zone of some Schwarzschild Black-Hole (BH). The densities of these
monopoles are calculated and quantized in the Dirac sense. This kind of duality
on the extended Einstein-Maxwell equations, relates electric and magnetic
charges on causally disconnected space regions.


title:
Size of the accretion disk in the gravitationally lensed quasar SDSS
  J1004+4112 from the statistics of microlensing magnifications

abstract:
  We present eight monitoring seasons of the four brightest images of the
gravitational lens SDSS J1004+4112 observed between December 2003 and October
2010. Using measured time delays for the images A, B and C and the model
predicted time delay for image D we have removed the intrinsic quasar
variability, finding microlensing events of about 0.5 and 0.7 mag of amplitude
in the images C and D. From the statistics of microlensing amplitudes in images
A, C, and D, we have inferred the half-light radius (at {\lambda} rest = 2407
{\AA}) for the accretion disk using two different methods,
$R_{1/2}=8.7^{+18.5}_{-5.5} \sqrt{M/0.3 M_\odot}$ (histograms product) and
$R_{1/2} = 4.2^{+3.2}_{-2.2} \sqrt{M/0.3 M_\odot}$ light-days ($\chi^2$). The
results are in agreement within uncertainties with the size predicted from the
black hole mass in SDSS J1004+4112 using the thin disk theory.


title:
On Minimal Accuracy Algorithm Selection in Computer Vision and
  Intelligent Systems

abstract:
  In this paper we discuss certain theoretical properties of algorithm
selection approach to image processing and to intelligent system in general. We
analyze the theoretical limits of algorithm selection with respect to the
algorithm selection accuracy. We show the theoretical formulation of a crisp
bound on the algorithm selector precision guaranteeing to always obtain better
than the best available algorithm result.


title: Stellar magnetism, winds and their effects on planetary environments

abstract:
  Here, I review some recent works on magnetism of cool, main-sequence stars,
their winds and potential impact on surrounding exoplanets. The winds of these
stars are very tenuous and persist during their lifetime. Although carrying
just a small fraction of the stellar mass, these magnetic winds carry away
angular momentum, thus regulating the rotation of the star. Since cool stars
are likely to be surrounded by planets, understanding the host star winds and
magnetism is a key step towards characterisation of exoplanetary environments.
As rotation and activity are intimately related, the spin down of stars leads
to a decrease in stellar activity with age. As a consequence, as stars age, a
decrease in high-energy (X-ray, extreme ultraviolet) irradiation is observed,
which can a ect the evaporation of exoplanetary atmospheres and, thus, also
altering exoplanetary evolution.


title:
Unifying interatomic potential, g(r), elasticity, viscosity, and
  fragility of metallic glasses: analytical model, simulations, and experiments

abstract:
  An analytical framework is proposed to describe the elasticity, viscosity and
fragility of metallic glasses in relation to their atomic-level structure and
the effective interatomic interaction. The bottom-up approach starts with
forming an effective Ashcroft-Born-Mayer interatomic potential based on
Boltzmann inversion of the radial distribution function g(r) and on fitting the
short-range part of $g(r)$ by means of a simple power-law approximation. The
power exponent $\lambda$ represents a global repulsion steepness parameter. A
scaling relation between atomic connectivity and packing fraction $Z \sim
\phi^{1+\lambda}$ is derived. This relation is then implemented in a
lattice-dynamical model for the high-frequency shear modulus where the
attractive anharmonic part of the effective interaction is taken into account
through the thermal expansion coefficient which maps the $\phi$-dependence into
a $T$-dependence. The shear modulus as a function of temperature calculated in
this way is then used within the cooperative shear model of the glass
transition to yield the viscosity of the supercooled melt as a
double-exponential function of $T$ across the entire Angell plot. The model,
which has only one adjustable parameter (the characteristic atomic volume for
high-frequency cage deformation) is tested against new experimental data of
ZrCu alloys and provides an excellent one-parameter description of the
viscosity down to the glass transition temperature.


title:
Universal scalings of N\'eel temperature, staggered magnetization
  density, and spinwave velocity of three-dimensional disordered and clean
  quantum antiferromagnets

abstract:
  The N\'eel temperature, staggered magnetization density, as well as the
spinwave velocity of a three-dimensional (3D) quantum Heisenberg model with
antiferromagnetic disorder (randomness) are calculated using first principles
non-perturbative quantum Monte Carlo simulations. In particular, we examine the
validity of universal scaling relations that are related to these three studied
physical quantities. These relations are relevant to experimental data and are
firmly established for clean (regular) 3D dimerized spin-1/2 Heisenberg models.
Remarkably, our numerical results show that the considered scaling relations
remain true for the investigated model with the introduced disorder. In
addition, while the presence of disorder may change the physical properties of
regular dimerized models, hence leading to different critical theories, both
the obtained data of N\'eel temperature and staggered magnetization density in
our study are fully compatible with the expected critical behaviour for clean
dimerized systems. As a result, it is persuasive to conclude that the related
quantum phase transitions of the considered disordered model and its clean
counterparts are governed by the same critical theory, which is not always the
case in general. Finally, we also find smooth scalings even emerging when both
the data of the investigated disordered model as well as its associated clean
system are taken into account. This in turn implies that, while in a restricted
sense, the considered scaling relations for 3D spin-1/2 antiferromagnets are
indeed universal.


title: Weight-adjusted discontinuous Galerkin methods: curvilinear meshes

abstract:
  Traditional time-domain discontinuous Galerkin (DG) methods result in large
storage costs at high orders of approximation due to the storage of dense
elemental matrices. In this work, we propose a weight-adjusted DG (WADG)
methods for curvilinear meshes which reduce storage costs while retaining
energy stability. A priori error estimates show that high order accuracy is
preserved under sufficient conditions on the mesh, which are illustrated
through convergence tests with different sequences of meshes. Numerical and
computational experiments verify the accuracy and performance of WADG for a
model problem on curved domains.


title:
A Local Relative Trace Formula for the Ginzburg-Rallis Model: the
  Geometric Side

abstract:
  Following the method developed by Waldspurger and Beuzart-Plessis in their
proofs of the local Gan-Gross-Prasad conjecture, we are able to prove the
geometric side of a local relative trace formula for the Ginzburg-Rallis model.
Then by applying such formula, we prove a multiplicity formula of the
Ginzburg-Rallis model for the supercuspidal representations. Using that
multiplicity formula, we prove the multiplicity one theorem for the
Ginzburg-Rallis model over Vogan packets in the supercuspidal case.


title: Exclusive J/psi and Upsilon photoproduction and the low x gluon

abstract:
  We discuss the potential to constrain the small-$x$ PDFs using the exclusive
production of heavy vector mesons. The calculation of $J/\psi$ and $\Upsilon$
photoproduction at NLO in collinear factorisation is described. The different
behaviour of the NLO corrections for $J/\psi$ and $\Upsilon$ is highlighted and
we outline what might be expected from the inclusion of these processes in a
PDF fit.


title: Mimicking dark matter in Horndeski gravity

abstract:
  Since the rediscovery of Horndeski gravity, a lot of work has been devoted to
the exploration of its properties, especially in the context of dark energy.
However, one sector of this theory, namely the one containing the coupling of
the Einstein tensor to the kinetic term of the scalar field, shows some
surprising features in the construction of black holes and neutron stars.
Motivated by these new results, I explore the possibility that this sector of
Horndeski gravity can mimic cold dark matter at cosmological level and also
explain the flattening of galactic rotation curves. I will show that, in
principle, it is possible to achieve both goals with at least two scalar fields
and a minimal set of assumptions.


title:
Multiplicity One Theorem for the Ginzburg-Rallis Model: the tempered
  case

abstract:
  Following the method developed by Waldspurger and Beuzart-Plessis in their
proof of the local Gan-Gross-Prasad conjecture, we are able to prove the
multiplicity one theorem for the Ginzburg-Rallis model over the Vogan packets
in the tempered case. In some cases, we can also relate the multiplicity to the
epsilon factor. This is a sequel of our work \cite{Wan15} in which we consider
the supercuspidal case.


title:
Volatiles beneath mid-ocean ridges: deep melting, channelised transport,
  focusing, and metasomatism

abstract:
  Deep-Earth volatile cycles couple the mantle with near-surface reservoirs.
Volatiles are emitted by volcanism and, in particular, from mid-ocean ridges,
which are the most prolific source of basaltic volcanism. Estimates of volatile
extraction from the asthenosphere beneath ridges typically rely on measurements
of undegassed lavas combined with simple petrogenetic models of the mean degree
of melting. Estimated volatile fluxes have large uncertainties; this is partly
due to a poor understanding of how volatiles are transported by magma in the
asthenosphere. Here, we assess the fate of mantle volatiles through numerical
simulations of melting and melt transport at mid-ocean ridges. Our simulations
are based on two-phase, magma/mantle dynamics theory coupled to idealised
thermodynamic model of mantle melting in the presence of water and carbon
dioxide. We combine simulation results with catalogued observations of all
ridge segments to estimate a range of likely volatile output from the global
mid-ocean ridge system. We thus predict global MOR crust production of 66-73
Gt/yr (22-24 km3/yr) and global volatile output of 52-110 Mt/yr, corresponding
to mantle volatile contents of 100--200~ppm. We find that volatile extraction
is limited: up to half of deep, volatile-rich melt is not focused to the axis
but is rather deposited along the LAB. As these distal melts crystallise and
fractionate, they metasomatise the base of the lithosphere, creating
rheological heterogeneity that could contribute to the seismic signature of the
LAB.


title:
Ultrafast inhomogeneous magnetization dynamics analyzed by
  interface-sensitive nonlinear magneto-optics

abstract:
  We analyze laser-induced ultrafast, spatially inhomogeneous magnetization
dynamics of epitaxial Co/Cu(001) films in a 0.4-10 nm thickness range with
time-resolved magnetization-induced second harmonic generation, which probes
femtosecond spin dynamics at the vacuum/Co and Co/Cu interfaces. The
interference of these two contributions makes the overall signal particularly
sensitive to differences in the transient magnetization redistribution between
the two interfaces, i.e. ultrafast magnetization profiles in the ferromagnetic
film. We find in films of up to 3 nm thickness a stronger demagnetization at
the surface, because the film thickness is smaller than the effective mean free
path of the spin current mediating the demagnetization, i.e. the difference
between the mean free paths of the majority and minority carriers. For film
thicknesses larger than 3 nm, the magnetization profile reverses, since
majority spins can escape into the conducting substrate only from the
interface-near region.