title: Secret sharing of a quantum state

abstract:
  Secret sharing of a quantum state, or quantum secret sharing, in which a
dealer wants to share certain amount of quantum information with a few players,
has wide applications in quantum information. The critical criterion in a
threshold secret sharing scheme is confidentiality, with less than the
designated number of players, no information can be recovered. Furthermore, in
a quantum scenario, one additional critical criterion exists, the capability of
sharing entangled and unknown quantum information. Here by employing a
six-photon entangled state, we demonstrate a quantum threshold scheme, where
the shared quantum secrecy can be efficiently reconstructed with a state
fidelity as high as 93%. By observing that any one or two parties cannot
recover the secrecy, we show that our scheme meets the confidentiality
criterion. Meanwhile, we also demonstrate that entangled quantum information
can be shared and recovered via our setting, which demonstrates that our
implemented scheme is fully quantum. Moreover, our experimental setup can be
treated as a decoding circuit of the 5-qubit quantum error-correcting code with
two erasure errors.


title:
Optimal processes for probabilistic work extraction beyond the second
  law

abstract:
  According to the second law of thermodynamics, for every transformation
performed on a system which is in contact with an environment of fixed
temperature, the extracted work is bounded by the decrease of the free energy
of the system. However, in a single realization of a generic process, the
extracted work is subject to statistical fluctuations which may allow for
probabilistic violations of the previous bound. We are interested in enhancing
this effect, i.e. we look for thermodynamic processes that maximize the
probability of extracting work above a given arbitrary threshold. For any
process obeying the Jarzynski identity, we determine an upper bound for the
work extraction probability that depends also on the minimum amount of work
that we are willing to extract in case of failure, or on the average work we
wish to extract from the system. Then we show that this bound can be saturated
within the thermodynamic formalism of quantum discrete processes composed by
sequences of unitary quenches and complete thermalizations. We explicitly
determine the optimal protocol which is given by two quasi-static isothermal
transformations separated by a finite unitary quench.


title: Accent Classification with Phonetic Vowel Representation

abstract:
  Previous accent classification research focused mainly on detecting accents
with pure acoustic information without recognizing accented speech. This work
combines phonetic knowledge such as vowels with acoustic information to build
Guassian Mixture Model (GMM) classifier with Perceptual Linear Predictive (PLP)
features, optimized by Hetroscedastic Linear Discriminant Analysis (HLDA). With
input about 20-second accented speech, this system achieves classification rate
of 51% on a 7-way classification system focusing on the major types of accents
in English, which is competitive to the state-of-the-art results in this field.


title:
Forward-backward quasi-Newton methods for nonsmooth optimization
  problems

abstract:
  The forward-backward splitting method (FBS) for minimizing a nonsmooth
composite function can be interpreted as a (variable-metric) gradient method
over a continuously differentiable function which we call forward-backward
envelope (FBE). This allows to extend algorithms for smooth unconstrained
optimization and apply them to nonsmooth (possibly constrained) problems. Since
the FBE and its gradient can be computed by simply evaluating forward-backward
steps, the resulting methods rely on the very same black-box oracle as FBS. We
propose an algorithmic scheme that enjoys the same global convergence
properties of FBS when the problem is convex, or when the objective function
possesses the Kurdyka-{\L}ojasiewicz property at its critical points. Moreover,
when using quasi-Newton directions the proposed method achieves superlinear
convergence provided that usual second-order sufficiency conditions on the FBE
hold at the limit point of the generated sequence. Such conditions translate
into milder requirements on the original function involving generalized
second-order differentiability. We show that BFGS fits our framework and that
the limited-memory variant L-BFGS is well suited for large-scale problems,
greatly outperforming FBS or its accelerated version in practice. The analysis
of superlinear convergence is based on an extension of the Dennis and Mor\'e
theorem for the proposed algorithmic scheme.


title:
Interpolation across a muffin-tin interstitial using localized linear
  combinations of spherical waves

abstract:
  A method for 3D interpolation between hard spheres is described. The function
to be interpolated could be the charge density between atoms in condensed
matter. Its electrostatic potential is found analytically, and so are various
integrals. Periodicity is not required. The interpolation functions are
localized structure-adapted linear combinations of spherical waves, socalled
unitary spherical waves (USWs), centered at the spheres where they have
cubic-harmonic character. Input to the interpolation are the coefficients in
the cubic-harmonic expansion of the target function at and slightly outside the
spheres; specifically, the values and 3 first radial derivatives. To fit this,
we use USWs with 4 negative energies. Each interpolation function is actually a
linear combination of these 4 sets of USWs with the following properties: (1)
It is centered at a specific sphere where it has a specific cubic-harmonic
character and radial derivative. (2) Its value and first 3 radial derivatives
vanish at all other spheres and for all other cubic-harmonics. It is therefore
highly localized. Explicit expressions are given for these value-and-derivative
(v&d) functions and their Coulomb potentials in terms of the USWs and their
structure matrix, including those with zero energy, as well as for integrals
over the interstitial of the v&d functions and of their products. Use of point-
and space-group symmetries can significantly reduce matrix sizes and the number
of v&d functions. For open structures, additional constraints are needed to
pinpoint the interpolated function deep in the interstitial. This requires the
USW set at one extra energy. As examples, we consider a constant density and
the valence-electron densities in zinc-blende structured Si, ZnSe, and CuBr.


title:
Local Uncertainty Sampling for Large-Scale Multi-Class Logistic
  Regression

abstract:
  A major challenge for building statistical models in the big data era is that
the available data volume far exceeds the computational capability. A common
approach for solving this problem is to employ a subsampled dataset that can be
handled by available computational resources. In this paper, we propose a
general subsampling scheme for large-scale multi-class logistic regression and
examine the variance of the resulting estimator. We show that asymptotically,
the proposed method always achieves a smaller variance than that of the uniform
random sampling. Moreover, when the classes are conditionally imbalanced,
significant improvement over uniform sampling can be achieved. Empirical
performance of the proposed method is compared to other methods on both
simulated and real-world datasets, and these results match and confirm our
theoretical analysis.


title: Updated scalar sector constraints in Higgs triplet model

abstract:
  We show that in the Higgs triplet model, after the Higgs discovery, the
mixing angle in the CP-even sector can be strongly constrained from unitarity.
We also discuss how large quantum effects in $h\to\gamma\gamma$ may arise in a
SM-like scenario and a certain part of the parameter space can be ruled out
from the diphoton signal strength. Using $T$-parameter and diphoton signal
strength measurements, we update the bounds on the nonstandard scalar masses.


title:
I. Dissociation free energies in drug-receptor systems via non
  equilibrium alchemical simulations: theoretical framework

abstract:
  In this contribution I critically revise the alchemical reversible approach
in the context of the statistical mechanics theory of non covalent bonding in
drug receptor systems. I show that most of the pitfalls and entanglements for
the binding free energies evaluation in computer simulations are rooted in the
equilibrium assumption that is implicit in the reversible method. These
critical issues can be resolved by using a non-equilibrium variant of the
alchemical method in molecular dynamics simulations, relying on the production
of many independent trajectories with a continuous dynamical evolution of an
externally driven alchemical coordinate, completing the decoupling of the
ligand in a matter of few tens of picoseconds rather than nanoseconds. The
absolute binding free energy can be recovered from the annihilation work
distributions by applying an unbiased unidirectional free energy estimate, on
the assumption that any observed work distribution is given by a mixture of
normal distributions, whose components are identical in either direction of the
non-equilibrium process, with weights regulated by the Crooks theorem. I
finally show that the inherent reliability and accuracy of the unidirectional
estimate of the decoupling free energies, based on the production of few
hundreds of non-equilibrium independent sub-nanoseconds unrestrained alchemical
annihilation processes, is a direct consequence of the funnel-like shape of the
free energy surface in molecular recognition. An application of the technique
on a real drug-receptor system is presented in the companion paper.


title: Heat meets light on the nanoscale

abstract:
  We discuss the state-of-the-art and remaining challenges in the fundamental
understanding and technology development for controlling light-matter
interactions in nanophotonic environments in and away from thermal equilibrium.
The topics covered range from the basics of the thermodynamics of light
emission and absorption, to applications in solar-thermal energy generation,
thermophotovoltaics, optical refrigeration, personalized cooling technologies,
development of coherent incandescent light sources, and spinoptics.


title: An ABC interpretation of the multiple auxiliary variable method

abstract:
  We show that the auxiliary variable method (M{\o}ller et al., 2006; Murray et
al., 2006) for inference of Markov random fields can be viewed as an
approximate Bayesian computation method for likelihood estimation.


title:
Field theoretical model of multi-layered Josephson junction and dynamics
  of Josephson vortices

abstract:
  Multi-layered Josephson junctions are modeled in the context of a field
theory, and dynamics of Josephson vortices trapped inside insulators are
studied. Starting from a theory consisting of complex and real scalar fields
coupled to a U(1) gauge field which admit parallel $N-1$ domain-wall solutions,
Josephson couplings are introduced weakly between the complex scalar fields.
The $N-1$ domain walls behave as insulators separating $N$ superconductors,
where one of the complex scalar fields has a gap. We construct the effective
Lagrangian on the domain walls, which reduces to a coupled sine-Gordon model
for well-separated walls We then construct sine-Gordon solitons emerging in an
effective theory in which we identify Josephson vortices carrying singly
quantized magnetic fluxes. When two neighboring superconductors tend to have
the same phase, the ground state does not change with the positions of domain
walls. On the other hand, when two neighboring superconductors tend to have
$\pi$-phase differences, the ground state has a phase transition depending on
the positions of domain walls; when the two walls are close to each other,
frustration occurs because of the coupling between the two superconductors
besides the thin superconductor. Focusing on the case of three superconductors
separated by two insulators, we find for the former case that the interaction
between two Josephson vortices on different insulators changes its nature,
i.e., attractive or repulsive, depending on the positions of the domain walls.
In the latter case, there emerges fractional Josephson vortices when two
degenerate ground states appear due to spontaneous charge-symmetry breaking,
and the number of the Josephson vortices varies with the position of the domain
walls. Our predictions should be verified in multilayered Josephson junctions.


title: A Low Complexity Encoding Algorithm for Systematic Polar Codes

abstract:
  Arikan has shown that systematic polar codes (SPC) outperform nonsystematic
polar codes (NSPC). However, the performance gain comes at the price of
elevated encoding complexity, i.e., compared to NSPC, the available encoding
methods for SPC require higher memory and computation. In this letter, we
propose an efficient encoding algorithm requiring only $N$ bits of memory and
having $\frac{N}{2}\log_2N$ XOR operations. Moreover, the auxiliary variables
in the algorithm can share the memory to reduce extra memory requirement.
Furthermore, a parallel 2-bit encoding algorithm is also presented to improve
the encoding throughput. Remarkably, we show that parallel encoding can be
implemented with the same number of XOR operations and memory bits. Finally,
the proposed encoding algorithm can be directly used for NSPC with the same
complexity.


title:
On the measurement problem with entangled photons and the possibility of
  local hidden variables

abstract:
  It is shown that there is no remote action with polarization measurements of
photons in singlet state. A model is presented introducing a hidden parameter
which determines the polarizer output. This model is able to explain the
polarization measurement results with entangled photons. It refutes Bell's
Theorem.


title: Homoclinic orbits in a porous pellet

abstract:
  The analysis performed as well as extensive numerical simulations have
revealed the possibility of the generation of homoclinic orbits as a result of
homoclinic bifurcation in a porous pellet. A method has been proposed for the
development of a special type of diagrams - the socalled bifurcation diagrams.
These diagrams comprise the locus of homoclinic orbits together with the lines
of limit points bounding the region of multiple steady states as well as the
locus of the points of Hopf bifurcation. Thus, they define a set of parameters
for which homoclinic bifurcation can take place. They also make it possible to
determine conditions under which homoclinic orbits are generated. Two kinds of
homoclinic orbits have been observed, namely semistable and unstable orbits. It
is found that the character of the homoclinic orbit depends on the stability
features of the limit cycle which is linked with the saddle point. Very
interesting dynamic phenomena are associated with the two kinds of homoclinic
orbits; these phenomena have been illustrated in the solution diagrams and
phase diagrams.


title: Local polar fluctuations in lead halide perovskite crystals

abstract:
  Hybrid lead-halide perovskites have emerged as an excellent class of
photovoltaic materials. Recent reports suggest that the organic molecular
cation is responsible for local polar fluctuations that inhibit carrier
recombination. We combine low frequency Raman scattering with first-principles
molecular dynamics (MD) to study the fundamental nature of these local polar
fluctuations. Our observations of a strong central peak in both hybrid
(CH$_3$NH$_3$PbBr$_3$) and all-inorganic (CsPbBr$_3$) lead-halide perovskites
show that anharmonic, local polar fluctuations are intrinsic to the general
lead-halide perovskite structure, and not unique to the dipolar organic cation.
MD simulations show that head-to-head Cs motion coupled to Br face expansion,
on a few hundred femtosecond time scale, drives the local polar fluctuations in
CsPbBr$_3$.


title:
An $\mathbf{\epsilon}$-pseudoclassical model for quantum resonances in a
  cold dilute atomic gas periodically driven by finite-duration standing-wave
  laser pulses

abstract:
  Atom interferometers are a useful tool for precision measurements of
fundamental physical phenomena, ranging from local gravitational field strength
to the atomic fine structure constant. In such experiments, it is desirable to
implement a high momentum transfer "beam-splitter," which may be achieved by
inducing quantum resonance in a finite-temperature laser-driven atomic gas. We
use Monte Carlo simulations to investigate these quantum resonances in the
regime where the gas receives laser pulses of finite duration, and demonstrate
that an $\epsilon$-classical model for the dynamics of the gas atoms is capable
of reproducing quantum resonant behavior for both zero-temperature and
finite-temperature non-interacting gases. We show that this model agrees well
with the fully quantum treatment of the system over a time-scale set by the
choice of experimental parameters. We also show that this model is capable of
correctly treating the time-reversal mechanism necessary for implementing an
interferometer with this physical configuration.

categories: quant-ph cond-mat.quant-gas nlin.CD physics.atom-ph


title:
Double-diffusive convection and baroclinic instability in a
  differentially heated and initially stratified rotating system: the barostrat
  instability

abstract:
  A water-filled differentially heated rotating annulus with initially prepared
stable vertical salinity profiles is studied in the laboratory. Based on
two-dimensional horizontal particle image velocimetry (PIV) data, and infrared
camera visualizations, we describe the appearance and the characteristics of
the baroclinic instability in this original configuration. First, we show that
when the salinity profile is linear and confined between two non stratified
layers at top and bottom, only two separate shallow fluid layers can be
destabilized. These unstable layers appear nearby the top and the bottom of the
tank with a stratified motionless zone between them. This laboratory
arrangement is thus particularly interesting to model geophysical or
astrophysical situations where stratified regions are often juxtaposed to
convective ones. Then, for more general but stable initial density profiles,
statistical measures are introduced to quantify the extent of the baroclinic
instability at given depths and to analyze the connections between this
depth-dependence and the vertical salinity profiles. We find that, although the
presence of stable stratification generally hinders full-depth overturning,
double-diffusive convection can yield development of multicellular sideways
convection in shallow layers and subsequently to a multilayered baroclinic
instability. Therefore we conclude that by decreasing the characteristic
vertical scale of the flow, stratification may even enhance the formation of
cyclonic and anticyclonic eddies (and thus, mixing) in a local sense.


title:
Correlation effects and collective excitations in bosonic bilayers: role
  of quantum statistics, superfluidity and dimerization transition

abstract:
  A two-component two-dimensional (2D) dipolar bosonic system in the bilayer
geometry is considered. By performing quantum Monte Carlo simulations in a wide
range of layer spacings we analyze in detail the pair correlation functions,
the static response function, the kinetic and interaction energies. By reducing
the layer spacing we observe a transition from weakly to strongly bound dimer
states. The transition is accompanied by the onset of short-range correlations,
suppression of the superfluid response, and rotonization of the excitation
spectrum. A dispersion law and a dynamic structure factor for the {\em
in-phase} (symmetric) and {\em out-of-phase} (antisymmetric) collective modes,
during the dimerization, is studied in detail with the stochastic
reconstruction method and the method of moments. The antisymmetric mode
spectrum is most strongly influenced by suppression of the inlayer
superfluidity (specified by the superfluid fraction $\gamma_s=\rho_s/\rho$). In
a pure superfluid/normal phase only an acoustic/optical(gapped) mode is
recovered. In a partially superfluid phase, both are present simultaneously,
and the dispersion splits into two branches corresponding to a normal and a
superfluid component. The spectral weight of the acoustic mode scales linearly
with $\gamma_s$. This weight transfers to the optical branch when $\gamma_s$ is
reduced due to formation of dimer states. In summary, we demonstrate how the
interlayer dimerization in dipolar bilayers can be uniquely identified by
static and dynamic properties.


title: Dirac matrices as elements of superalgebraic matrix algebra

abstract:
  The paper considers a Clifford extension of the Grassmann algebra, in which
operators are built from Grassmann variables and by the derivatives with
respect to them. It is shown that a subalgebra which is isomorphic to the usual
matrix algebra exists in this algebra, the Clifford exten-sion of the Grassmann
algebra is a generalization of the matrix algebra and contains superalgebraic
operators expanding matrix algebra and produces supersymmetric transformations.


title:
An Information Physics Derivation of Equations of Geodesic Form from the
  Influence Network

abstract:
  Information physics considers physical laws to result from the consistent
quantification and processing of information about physical phenomena. In
previous efforts, one of us (Knuth) has shown that a simple model of particles
that directly influence one another results in a partially ordered set referred
to as the influence network, from which emerge the Minkowski metric and Lorentz
transformations of special relativity. Here, we extend earlier work on receipt
of influence to the case of one particle influencing another, finding that this
gives rise to equations of the form of geodesic equations from general
relativity in 1+1 dimensions. Future work will test the equivalence of the
current result to general relativity in 1+1 dimensions.


title: On the general constraints in single qubit quantum process tomography

abstract:
  We briefly review single-qubit quantum process tomography for
trace-preserving and nontrace-preserving processes, and derive explicit forms
of the general constraints for fitting experimental data. These new forms
provide additional insight into the structure of the process matrix. We
illustrate their utility with several examples, including a discussion of qubit
leakage error models and the intuition which can be gained from their process
matrices.


title: Photon Bubble Turbulence in Cold Atom Gases

abstract:
  Turbulent radiation flow is commonplace in systems with strong, incoherent,
light-matter interactions. In astrophysical contexts, photon bubble turbulence
is considered a key mechanism behind enhanced radiation transport, and its
importance has been widely asserted for a variety of high energy objects such
as accretion disks and massive stars. We demonstrate here that analogous
conditions to those of dense astrophysical objects can be obtained in large
clouds of cold atoms driven close to a sharp electronic resonance. By accessing
the spatially-resolved atom density, we are able to identify a photon bubble
instability and the resulting regime of photon bubble turbulence. We also
develop a theoretical model describing the coupled dynamics of both photon and
atom gases, which accurately describes the statistical properties of the
turbulent regime. This study thus opens the possibility of simulating
radiation-dominated astrophysical systems in cold atom experiments.

categories: physics.atom-ph astro-ph.SR physics.flu-dyn quant-ph


title: Scanning micro-resonator direct-comb absolute spectroscopy

abstract:
  Direct optical frequency Comb Spectroscopy (DCS) is proving to be a
fundamental tool in many areas of science and technology thanks to its unique
performance in terms of ultra-broadband, high-speed detection and frequency
accuracy, allowing for high-fidelity mapping of atomic and molecular energy
structure. Here we present a novel DCS approach based on a scanning Fabry-Perot
micro-cavity resonator (SMART) providing a simple, compact and accurate method
to resolve the mode structure of an optical frequency comb. The SMART approach,
while drastically reducing system complexity, allows for a straightforward
absolute calibration of the optical-frequency axis with an ultimate resolution
limited by the micro-resonator resonance linewidth and can be used in any
spectral region from XUV to THz. An application to high-precision spectroscopy
of acetylene at 1.54 um is presented, demonstrating frequency resolution as low
as 20 MHz with a single-scan optical bandwidth up to 1 THz in 20-ms measurement
time and a noise-equivalent-absorption level per comb mode of 2.7 10^-9 cm^-1
Hz^(-1/2). Using higher finesse micro-resonators along with an enhancement
cavity, this technique has the potential to improve by more than one order of
magnitude the noise equivalent absorption in a multiterahertz spectral interval
with unchanged frequency resolution.


title:
The stellar metallicity gradients in galaxy discs in a cosmological
  scenario

abstract:
  The stellar metallicity gradients of disc galaxies provide information on the
disc assembly, star formation processes and chemical evolution. They also might
store information on dynamical processes which could affect the distribution of
chemical elements in the gas-phase and the stellar components. We studied the
stellar metallicity gradients of stellar discs in a cosmological simulation. We
explored the dependence of the stellar metallicity gradients on stellar age and
the size and mass of the stellar discs. We used galaxies selected from a
cosmological hydrodynamical simulation performed including a
physically-motivated Supernova feedback and chemical evolution. The metallicity
profiles were estimated for stars with different ages. We confront our
numerical findings with results from the CALIFA Survey. The simulated stellar
discs are found to have metallicity profiles with slopes in global agreement
with observations. Low stellar-mass galaxies tend to have a larger variety of
metallicity slopes. When normalized by the half-mass radius, the stellar
metallicity gradients do not show any dependence and the dispersion increases
significantly, regardless of galaxy mass. Galaxies with stellar masses around
$10^{10}$M$_{\odot}$ show steeper negative metallicity gradients. The stellar
metallicity gradients correlate with the half-mass radius. However, the
correlation signal is not present when they are normalized by the half-mass
radius. Stellar discs with positive age gradients are detected to have negative
and positive metallicity gradients, depending on the relative importance of the
recent star formation activity in the central regions. The large dispersions in
the metallicity gradients as a function of stellar mass could be ascribed to
the effects of dynamical processes such as mergers/interactions and/or
migration as well as those regulating the conversion of gas into stars.
[abridged]


title: Slow waves in locally resonant metamaterials line defect waveguides

abstract:
  In the past decades, many efforts have been devoted to the temporal
manipulation of waves, especially focusing on slowing down their propagation.
In electromagnetism, from microwave to optics, as well as in acoustics or for
elastic waves, slow wave propagation indeed largely benefits both applied and
fundamental physics. It is for instance essential in analog signal computing
through the design of components such as delay lines and buffers, and it is one
of the prerequisite for increased wave/matter interactions. Despite the
interest of a broad community, researches have mostly been conducted in optics
along with the development of wavelength scaled structured composite media,
that appear promising candidates for compact slow light components. Yet their
minimum structural scale prevents them from being transposed to lower
frequencies where wavelengths range from sub-millimeter to meters. In this
article, we propose to overcome this limitation thanks to the deep
sub-wavelength scale of locally resonant metamaterials. In our approach,
implemented here in the microwave regime, we show that introducing coupled
resonant defects in such composite media allows the creation of deep
sub-wavelength waveguides. We experimentally demonstrate that waves, while
propagating in such waveguides, exhibit largely reduced group velocities. We
qualitatively explain the mechanism underlying this slow wave propagation and
first experimentally demonstrate, then numerically verify, how it can be taken
advantage of to tune the velocity, achieving group indices ng as high as 227
over relatively large bandwidths. We conclude by highlighting the three
beneficial consequences of our line defect slow wave waveguides in locally
resonant metamaterials: the deep sub-wavelength scale, the very large group
indices and the fact that slow wave propagation does not occur at the expense
of drastic bandwidth reductions.


title:
On spectral gap properties and extreme value theory for multivariate
  affine stochastic recursions

abstract:
  We consider a general multivariate affine stochastic recursion and the
associated Markov chain on $\mathbb R^{d}$. We assume a natural geometric
condition which implies existence of an unbounded stationary solution and we
show that the large values of the associated stationary process follow extreme
value properties of classical type, with a non trivial extremal index. We
develop some explicit consequences such as convergence to Fr{\'e}chet's law or
to an exponential law, as well as convergence to a stable law. The proof is
based on a spectral gap property for the action of associated positive
operators on spaces of regular functions with slow growth, and on the
clustering properties of large values in the recursion.


title: Spider Silk: The Mother Nature's Biological Superlens

abstract:
  This paper demonstrates a possible new microfiber bio near field lens that
uses minor ampullate spider silk,spun from the Nephila edulis spider, to create
a real time image of a surface using near field optical techniques. The
microfiber bio lens is the world's first natural superlens created by exploring
biological materials. The resolution of the surface image overcomes the
diffraction limit, with the ability to resolve patterns at 100 nm under a
standard white light source in reflection mode. This resolution offers further
developments in superlens technology and paves the way for new bio optics.


title: Extracting Temporal and Causal Relations between Events

abstract:
  Structured information resulting from temporal information processing is
crucial for a variety of natural language processing tasks, for instance to
generate timeline summarization of events from news documents, or to answer
temporal/causal-related questions about some events. In this thesis we present
a framework for an integrated temporal and causal relation extraction system.
We first develop a robust extraction component for each type of relations, i.e.
temporal order and causality. We then combine the two extraction components
into an integrated relation extraction system, CATENA---CAusal and Temporal
relation Extraction from NAtural language texts---, by utilizing the
presumption about event precedence in causality, that causing events must
happened BEFORE resulting events. Several resources and techniques to improve
our relation extraction systems are also discussed, including word embeddings
and training data expansion. Finally, we report our adaptation efforts of
temporal information processing for languages other than English, namely
Italian and Indonesian.


title: On Polynomial Approximations to ${AC}^0$

abstract:
  We make progress on some questions related to polynomial approximations of
${\rm AC}^0$. It is known, by works of Tarui (Theoret. Comput. Sci. 1993) and
Beigel, Reingold, and Spielman (Proc. $6$th CCC, 1991), that any ${\rm AC}^0$
circuit of size $s$ and depth $d$ has an $\varepsilon$-error probabilistic
polynomial over the reals of degree $(\log (s/\varepsilon))^{O(d)}$. We improve
this upper bound to $(\log s)^{O(d)}\cdot \log(1/\varepsilon)$, which is much
better for small values of $\varepsilon$.
  We give an application of this result by using it to resolve a question posed
by Tal (ECCC 2014): we show that $(\log s)^{O(d)}\cdot
\log(1/\varepsilon)$-wise independence fools ${\rm AC}^0$, improving on Tal's
strengthening of Braverman's theorem (J. ACM, 2010) that $(\log
(s/\varepsilon))^{O(d)}$-wise independence fools ${\rm AC}^0$. Up to the
constant implicit in the $O(d)$, our result is tight. As far as we know, this
is the first PRG construction for ${\rm AC}^0$ that achieves optimal dependence
on the error $\varepsilon$.
  We also prove lower bounds on the best polynomial approximations to ${\rm
AC}^0$. We show that any polynomial approximating the ${\rm OR}$ function on
$n$ bits to a small constant error must have degree at least
$\widetilde{\Omega}(\sqrt{\log n})$. This result improves exponentially on a
recent lower bound demonstrated by Meka, Nguyen, and Vu (arXiv 2015).


title: Top physics at high-energy lepton colliders

abstract:
  A summary is presented of the workshop "top physics at linear colliders" that
was held at IFIC Valencia from the 30th of June to the 3rd July 2015. We
present an up-to-date status report of studies into the potential for top quark
physics of lepton colliders with an energy reach that exceeds the top quark
pair production threshold, with a focus on the linear collider projects ILC and
CLIC. This summary shows that such projects can offer very competitive
determinations of top quark properties (mass, width) and its interactions with
other Standard Model particles, in particular electroweak gauge bosons and the
Higgs boson. In both areas the prospects exceed the LHC potential significantly
- often by an order of magnitude.


title: Hybrid Analog-Digital Precoding Revisited under Realistic RF Modeling

abstract:
  In this paper we revisit hybrid analog-digital precoding systems with
emphasis on their modelling and radio-frequency (RF) losses, to realistically
evaluate their benefits in 5G system implementations. For this, we decompose
the analog beamforming networks (ABFN) as a bank of commonly used RF components
and formulate realistic model constraints based on their S-parameters.
Specifically, we concentrate on fully-connected ABFN (FC-ABFN) and Butler
networks for implementing the discrete Fourier transform (DFT) in the RF
domain. The results presented in this paper reveal that the performance and
energy efficiency of hybrid precoding systems are severely affected, once
practical factors are considered in the overall design. In this context, we
also show that Butler RF networks are capable of providing better performances
than FC-ABFN for systems with a large number of RF chains.


title: Quasicrystals: Making invisible materials

abstract:
  All-dielectric photonic quasicrystals may act as zero-refractive-index
homogeneous materials despite their lack of translational symmetry and
periodicity, stretching wavelengths to infinity and offering applications in
light wavefront sculpting and optical cloaking.


title: Hiring Secretaries over Time: The Benefit of Concurrent Employment

abstract:
  We consider a stochastic online problem where $n$ applicants arrive over
time, one per time step. Upon arrival of each applicant their cost per time
step is revealed, and we have to fix the duration of employment, starting
immediately. This decision is irrevocable, i.e., we can neither extend a
contract nor dismiss a candidate once hired. In every time step, at least one
candidate needs to be under contract, and our goal is to minimize the total
hiring cost, which is the sum of the applicants' costs multiplied with their
respective employment durations. We provide a competitive online algorithm for
the case that the applicants' costs are drawn independently from a known
distribution. Specifically, the algorithm achieves a competitive ratio of 2.965
for the case of uniform distributions. For this case, we give an analytical
lower bound of 2 and a computational lower bound of 2.148. We then adapt our
algorithm to stay competitive even in settings with one or more of the
following restrictions: (i) at most two applicants can be hired concurrently;
(ii) the distribution of the applicants' costs is unknown; (iii) the total
number $n$ of time steps is unknown. On the other hand, we show that concurrent
employment is a necessary feature of competitive algorithms by proving that no
algorithm has a competitive ratio better than $\Omega(\sqrt{n} / \log n)$ if
concurrent employment is forbidden.


title:
Unified ab initio formulation of flexoelectricity and strain-gradient
  elasticity

abstract:
  The theories of flexoelectricity and that of nonlocal elasticity are closely
related, and are often considered together when modeling strain-gradient
effects in solids. Here I show, based on a first-principles lattice-dynamical
analysis, that their relationship is much more intimate than previously
thought, and their consistent simultaneous treatment is crucial for obtaining
correct physical answers. In particular, I identify a gauge invariance in the
theory, whereby the energies associated to strain-gradient elasticity and
flexoelectrically induced electric fields are individually reference-dependent,
and only when summed up they yield a well-defined result. To illustrate this, I
construct a minimal thermodynamic functional incorporating strain-gradient
effects, and establish a formal link between the continuum description and ab
initio phonon dispersion curves to calculate the relevant tensor quantities. As
a practical demonstration, I apply such a formalism to bulk SrTiO$_3$, where I
find an unusually strong contribution of nonlocal elasticity, mediated by the
interaction between the ferroelectric soft mode and the transverse acoustic
branches. These results have important implications towards the construction of
well-defined thermodynamic theories where flexoelectricity and ferroelectricity
coexist. More generally, they open exciting new avenues for the implementation
of hierarchical multiscale concepts in the first-principles simulation of
crystalline insulators.


title:
Partially Observed Markov Decision Processes. Problem Sets and Internet
  Supplement

abstract:
  This document is an internet supplement to my book "Partially Observed Markov
Decision Processes - From Filtering to Controlled Sensing" published by
Cambridge University Press in 2016. This internet supplement contains
exercises, examples and case studies. The material appears in this internet
supplement (instead of the book) so that it can be updated. This document will
evolve over time and further discussion and examples will be added. This
internet supplement document is work in progress and will be updated
periodically. I welcome constructive comments from readers of the book and this
internet supplement.


title: The dynamic adsorption of Xe on a fixed bed adsorber at 77 K

abstract:
  During the design of fixed bed adsorbers, it is vital to understand the
dynamic adsorption properties of the system. Because temperature is one of the
most important factors affecting adsorbent performance, such that the dynamic
adsorption coefficients tend to increase as the temperature decreases, the
dynamic adsorption characteristics of Xe on a fixed bed adsorber at 77 K were
studied in the present work to minimize the volume of fixed bed adsorber,
employing a variety of adsorbents under different operational conditions. The
results show that the adsorption performance of carbon molecular sieve is
superior to that of activated carbon. And both operational conditions and the
presence of gaseous impurities were found to affect adsorption properties.


title:
Evolution in totally constrained models: Schr\"odinger vs. Heisenberg
  pictures

abstract:
  We study the relation between two evolution pictures that are currently
considered for totally constrained theories. Both descriptions are based on
Rovelli's evolving constants approach, where one identifies a (possibly local)
degree of freedom of the system as an internal time. This method is well
understood classically in several situations. The purpose of this paper is to
further analyze this approach at the quantum level. Concretely, we will compare
the (Schr\"odinger-like) picture where the physical states evolve in time with
the (Heisenberg-like) picture in which one defines parametrized observables (or
evolving constants of the motion). We will show that in the particular
situations considered in this manuscript (the parametrized relativistic
particle and a spatially flat homogeneous and isotropic spacetime coupled to a
massless scalar field) both descriptions are equivalent. We will finally
comment on possible issues and on the genericness of the equivalence between
both pictures.


title:
Enhancement and tunability of near-field radiative heat transfer
  mediated by surface plasmon polaritons in thin plasmonic films

abstract:
  The properties of thermal radiation exchange between hot and cold objects can
be strongly modified if they interact in the near field where electromagnetic
coupling occurs across gaps narrower than the dominant wavelength of thermal
radiation. Using a rigorous fluctuational electrodynamics approach, we predict
that ultra-thin films of plasmonic materials can be used to dramatically
enhance near-field heat transfer. The total spectrally integrated film-to-film
heat transfer is over an order of magnitude larger than between the same
materials in bulk form and also exceeds the levels achievable with polar
dielectrics such as SiC. We attribute this enhancement to the significant
spectral broadening of radiative heat transfer due to coupling between surface
plasmon polaritons (SPPs) on both sides of each thin film. We show that the
radiative heat flux spectrum can be further shaped by the choice of the
substrate onto which the thin film is deposited. In particular, substrates
supporting surface phonon polaritons (SPhP) strongly modify the heat flux
spectrum owing to the interactions between SPPs on thin films and SPhPs of the
substrate. The use of thin film phase change materials on polar dielectric
substrates allows for dynamic switching of the heat flux spectrum between
SPP-mediated and SPhP-mediated peaks.


title:
Revisiting the Contributions of Supernova and Hypernova Remnants to the
  Diffuse High-Energy Backgrounds: Constraints on Very-High-Redshift Injections

abstract:
  Star-forming and starburst galaxies are considered as one of the viable
candidate sources of the high-energy cosmic neutrino background detected in
IceCube. We revisit contributions of supernova remnants (SNRs) and hypernova
remnants (HNRs) in such galaxies to the diffuse high-energy neutrino and
gamma-ray backgrounds, in light of the latest Fermi data above 50GeV. We also
take into account possible time dependent effects of the cosmic-ray (CR)
acceleration during the SNR evolution. CRs accelerated by the SNR shocks can
produce high-energy neutrinos up to $\sim100$ TeV energies, but CRs from HNRs
can extend the spectrum up to PeV energies. We show that, only if HNRs are
dominant over SNRs, the diffuse neutrino background above 100 TeV can be
explained without contradicting the gamma-ray data. However, the neutrino data
around 30 TeV remain unexplained, which might suggest a different population of
gamma-ray dark CR sources. Alternatively, we consider possible contributions of
Pop-III HNRs up to $z\lesssim10$, and show that they are not constrained by the
gamma-ray data, and thus could contribute to the diffuse high-energy
backgrounds if their explosion energy reaches ${\mathcal E}_{\rm
POP-III}\sim{\rm a~few}\times10^{53}$erg. More conservatively, our results
suggest that the explosion energy of POP-III HNRs is ${\mathcal E}_{\rm
POP-III}\lesssim7\times{10}^{53}$erg.


title:
A Logarithmic Integrality Gap Bound for Directed Steiner Tree in
  Quasi-bipartite Graphs

abstract:
  We demonstrate that the integrality gap of the natural cut-based LP
relaxation for the directed Steiner tree problem is $O(\log k)$ in
quasi-bipartite graphs with $k$ terminals. Such instances can be seen to
generalize set cover, so the integrality gap analysis is tight up to a constant
factor. A novel aspect of our approach is that we use the primal-dual method; a
technique that is rarely used in designing approximation algorithms for network
design problems in directed graphs.


title:
Reflection Of Propagating Slow Magneto-acoustic Waves In Hot Coronal
  Loops : Multi-instrument Observations and Numerical Modelling

abstract:
  Slow MHD waves are important tools for understanding the coronal structures
and dynamics. In this paper, we report a number of observations, from X-Ray
Telescope (XRT) on board HINODE and SDO/AIA of reflecting longitudinal waves in
hot coronal loops. To our knowledge, this is the first report of this kind as
seen from the XRT and simultaneously with the AIA. The wave appears after a
micro-flare occurs at one of the footpoints. We estimate the density and the
temperature of the loop plasma by performing DEM analysis on the AIA image
sequence. The estimated speed of propagation is comparable or lower than the
local sound speed suggesting it to be a propagating slow wave. The intensity
perturbation amplitudes, in every case, falls very rapidly as the perturbation
moves along the loop and eventually vanishes after one or more reflections. To
check the consistency of such reflection signatures with the obtained loop
parameters, we perform a 2.5D MHD simulation, which uses the parameters
obtained from our observation as inputs and performed forward modelling to
synthesize AIA 94~\r{A} images. Analyzing the synthesized images, we obtain the
same properties of the observables as for the real observation. From the
analysis we conclude that a footpoint heating can generate slow wave which then
reflects back and forth in the coronal loop before fading out. Our analysis on
the simulated data shows that the main agent for this damping is the
anisotropic thermal conduction.


title:
Kinesin-8 effects on mitotic microtubule dynamics contribute to spindle
  function in fission yeast

abstract:
  Kinesin-8 motor proteins destabilize microtubules. Their absence during cell
division is associated with disorganized mitotic chromosome movements and
chromosome loss. Despite recent work studying effects of kinesin 8s on
microtubule dynamics, it remains unclear whether the kinesin-8 mitotic
phenotypes are consequences of their effect on microtubule dynamics, their
well-established motor activity, or additional unknown functions. To better
understand the role of kinesin-8 proteins in mitosis, we have studied the
effects of deletion of the fission-yeast kinesin-8 proteins Klp5 and Klp6 on
chromosome movements and spindle length dynamics. Aberrant microtubule-driven
kinetochore pushing movements and tripolar mitotic spindles occurred in cells
lacking Klp5 but not Klp6. Kinesin-8 deletion strains showed large fluctuations
in metaphase spindle length, suggesting a disruption of spindle length
stabilization. Comparison of our results from light microscopy with a
mathematical model suggests that kinesin-8 induced effects on microtubule
dynamics, kinetochore attachment stability, and sliding force in the spindle
can explain the aberrant chromosome movements and spindle length fluctuations
seen.


title: Harmonic chain with velocity flips: thermalization and kinetic theory

abstract:
  We consider the detailed structure of correlations in harmonic chains with
pinning and a bulk velocity flip noise during the heat relaxation phase which
occurs on diffusive time scales, for $t=O(L^2)$ where $L$ is the chain length.
It has been shown earlier that for non-degenerate harmonic interactions these
systems thermalize, and the dominant part of the correlations is given by local
thermal equilibrium determined by a temperature profile which satisfies a
linear heat equation. Here we are concerned with two new aspects about the
thermalization process: the first order corrections in $1/L$ to the local
equilibrium correlations and the applicability of kinetic theory to study the
relaxation process. Employing previously derived explicit uniform estimates for
the temperature profile, we first derive an explicit form for the first order
corrections to the particle position-momentum correlations. By suitably
revising the definition of the Wigner transform and the kinetic scaling limit
we derive a phonon Boltzmann equation whose predictions agree with the explicit
computation. Comparing the two results, the corrections can be understood as
arising from two different sources: a current-related term and a correction to
the position-position correlations related to spatial changes in the phonon
eigenbasis.


title:
Collective Stochastic Discrete Choice Problems: A Min-LQG Game
  Formulation

abstract:
  We consider a class of dynamic collective choice models with social
interactions, whereby a large number of non-uniform agents have to individually
settle on one of multiple discrete alternative choices, with the relevance of
their would-be choices continuously impacted by noise and the unfolding group
behavior. This class of problems is modeled here as a so-called Min-LQG game,
i.e., a linear quadratic Gaussian dynamic and non-cooperative game, with an
additional combinatorial aspect in that it includes a final choice-related
minimization in its terminal cost. The presence of this minimization term is
key to enforcing some specific discrete choice by each individual agent. The
theory of mean field games is invoked to generate a class of decentralized
agent feedback control strategies which are then shown to converge to an exact
Nash equilibrium of the game as the number of players increases to infinity. A
key building block in our approach is an explicit solution to the problem of
computing the best response of a generic agent to some arbitrarily posited
smooth mean field trajectory. Ultimately, an agent is shown to face a
continuously revised discrete choice problem, where greedy choices dictated by
current conditions must be constantly balanced against the risk of the future
process noise upsetting the wisdom of such decisions.Even though an agent's
ultimately chosen alternative is random and dictated by its entire noise
history and initial state, the limiting infinite population macroscopic
behavior can still be predicted. It is shown that any Nash equilibrium of the
game is defined by an a priori computable probability matrix characterizing the
manner in which the agent population ultimately splits among the available
alternatives.


title: On the mediation of program allocation in high-demand environments

abstract:
  In this paper we challenge the widely accepted premise that, in order to
carry out a distributed computation, say on the cloud, users have to inform,
along with all the inputs that the algorithm in use requires, the number of
processors to be used. We discuss the complicated nature of deciding the value
of such parameter, should it be chosen optimally, and propose the alternative
scenario in which this choice is passed on to the server side for automatic
determination. We show that the allocation problem arising from this
alternative is NP-hard only weakly, being therefore solvable in
pseudo-polynomial time. In our proposal, one key component on which the
automatic determination of the number of processors is based is the cost model.
The one we use, which is being increasingly adopted in the wake of the
cloud-computing movement, posits that each single execution of a program is to
be subject to current circumstances on both user and server side, and as such
be priced independently of all others. Running through our proposal is thus a
critique of the established common sense that sizing a set of processors to
handle a submission to some provider is entirely up to the user.


title: Dual-fermion approach to the Anderson-Hubbard model

abstract:
  We apply the recently developed dual fermion algorithm for disordered
interacting systems to the Anderson-Hubbard model. This algorithm is compared
with dynamical cluster approximation calculations for a one-dimensional system
to establish the quality of the approximation in comparison with an established
cluster method. We continue with a three-dimensional (3d) system and look at
the antiferromagnetic, Mott and Anderson localization transitions. The dual
fermion approach leads to quantitative as well as qualitative improvement of
the dynamical mean-field results and it allows one to calculate the hysteresis
in the double occupancy in 3d taking into account nonlocal correlations.


title: The integration of angular velocity

abstract:
  A common problem in physics and engineering is determination of the
orientation of an object given its angular velocity. When the direction of the
angular velocity changes in time, this is a nontrivial problem involving
coupled differential equations. Several possible approaches are examined, along
with various improvements over previous efforts. These are then evaluated
numerically by comparison to a complicated but analytically known rotation that
is motivated by the important astrophysical problem of precessing black-hole
binaries. It is shown that a straightforward solution directly using
quaternions is most efficient and accurate, and that the norm of the quaternion
is irrelevant. Integration of the generator of the rotation can also be made
roughly as efficient as integration of the rotation. Both methods will
typically be twice as efficient as naive vector- or matrix-based methods.
Implementation by means of standard general-purpose numerical integrators is
stable and efficient, so that such problems can be readily solved as part of a
larger system of differential equations. Possible generalization to integration
in other Lie groups is also discussed.


title: How should spin-weighted spherical functions be defined?

abstract:
  Spin-weighted spherical functions provide a useful tool for analyzing
tensor-valued functions on the sphere. A tensor field can be decomposed into
complex-valued functions by taking contractions with tangent vectors on the
sphere and the normal to the sphere. These component functions are usually
presented as functions on the sphere itself, but this requires an implicit
choice of distinguished tangent vectors with which to contract. Thus, we may
more accurately say that spin-weighted spherical functions are functions of
both a point on the sphere and a choice of frame in the tangent space at that
point. The distinction becomes extremely important when transforming the
coordinates in which these functions are expressed, because the implicit choice
of frame will also transform. Here, it is proposed that spin-weighted spherical
functions should be treated as functions on the spin group. This approach more
cleanly reflects the geometry involved, and allows for a more elegant
description of the behavior of spin-weighted functions. In this form, the
spin-weighted spherical harmonics have simple expressions as elements of the
Wigner $\mathfrak{D}$ representations, and transformations under rotation are
simple. Two variants of the angular-momentum operator are defined directly in
terms of the spin group; one is the standard angular-momentum operator
$\mathbf{L}$, while the other is shown to be related to the spin-raising
operator $\eth$. Computer code is also included, providing an explicit
implementation of the spin-weighted spherical harmonics in this form.


title:
Quantum quenches to the attractive one-dimensional Bose gas: exact
  results

abstract:
  We study quantum quenches to the one-dimensional Bose gas with attractive
interactions in the case when the initial state is an ideal one-dimensional
Bose condensate. We focus on properties of the stationary state reached at late
times after the quench. This displays a finite density of multi-particle bound
states, whose rapidity distribution is determined exactly by means of the
quench action method. We discuss the relevance of the multi-particle bound
states for the physical properties of the system, computing in particular the
stationary value of the local pair correlation function $g_2$.


title: Compensated semimetal LaSb with unsaturated magnetoresistance

abstract:
  By combining angle-resolved photoemission spectroscopy and quantum
oscillation measurements, we performed a comprehensive investigation on the
electronic structure of LaSb, which exhibits near-quadratic extremely large
magnetoresistance (XMR) without any sign of saturation at magnetic fields as
high as 40 T. We clearly resolve one spherical and one intersecting-ellipsoidal
hole Fermi surfaces (FSs) at the Brillouin zone (BZ) center $\Gamma$ and one
ellipsoidal electron FS at the BZ boundary $X$. The hole and electron carriers
calculated from the enclosed FS volumes are perfectly compensated, and the
carrier compensation is unaffected by temperature. We further reveal that LaSb
is topologically trivial but share many similarities with the Weyl semimetal
TaAs family in the bulk electronic structure. Based on these results, we have
examined the mechanisms that have been proposed so far to explain the
near-quadratic XMR in semimetals.


title: Shell structure from nuclear observables

abstract:
  The appearance and disappearance of shells and subshells are determined using
a previously introduced method of structural analysis. This work extends the
approach and applies it to protons, in addition to neutrons, in an attempt to
provide a more complete understanding of shell structure in nuclei.
Experimental observables including the mean-square charge radius, as well as
other spectroscopic and mass related quantities are analyzed for extrema. This
analysis also uses differential observables among adjacent even-even nuclei to
serve as the derivatives for these quantities of interest. Local extrema in
these quantities indicate shell structure and the lack of local extrema
indicate missing shell closures. The shell structure of low-mass nuclei is
inconsistent likely as a consequence of the single-particle structure.
Additionally, multiple shell features occurring in midshell regions are
determined by combining information from two or more observables. Our results
near stability complement previous observations further out.


title: Breaking graph symmetries by edge colourings

abstract:
  The distinguishing index $D'(G)$ of a graph $G$ is the least number of
colours needed in an edge colouring which is not preserved by any non-trivial
automorphism. Broere and Pil\'sniak conjectured that if every non-trivial
automorphism of a countable graph $G$ moves infinitely many edges, then $D'(G)
\leq 2$. We prove this conjecture.


title:
Laser light-field fusion for wide-field lensfree on-chip phase contrast
  nanoscopy

abstract:
  Wide-field lensfree on-chip microscopy, which leverages holography principles
to capture interferometric light-field encodings without lenses, is an emerging
imaging modality with widespread interest given the large field-of-view
compared to lens-based techniques. In this study, we introduce the idea of
laser light-field fusion for lensfree on-chip phase contrast nanoscopy, where
interferometric laser light-field encodings acquired using an on-chip setup
with laser pulsations at different wavelengths are fused to produce marker-free
phase contrast images of superior quality with resolving power more than five
times below the pixel pitch of the sensor array and more than 40% beyond the
diffraction limit. As a proof of concept, we demonstrate, for the first time, a
wide-field lensfree on-chip instrument successfully detecting 300 nm particles,
resulting in a numerical aperture of 1.1, across a large field-of-view of
$\sim$ 30 mm$^2$ without any specialized or intricate sample preparation, or
the use of synthetic aperture- or shift-based techniques.


title: Acoustojet: acoustic analogue of photonic jet phenomenon

abstract:
  It has been demonstrated for the first time that an existence of acoustic
analogue of photonic jet phenomenon, called acoustojet, providing for
subwavelength localization of acoustic field in the shadow area of arbitrary 3D
penetrable mesoscale particle, is possible.


title:
Tree-Deletion Pruning in Label-Correcting Algorithms for the
  Multiobjective Shortest Path Problem

abstract:
  In this paper, we re-evaluate the basic strategies for label correcting
algorithms for the multiobjective shortest path (MOSP) problem, i.e., node and
label selection. In contrast to common believe, we show that---when carefully
implemented---the node-selection strategy usually beats the label-selection
strategy. Moreover, we present a new pruning method which is easy to implement
and performs very well on real-world road networks. In this study, we test our
hypotheses on artificial MOSP instances from the literature with up to 15
objectives and real-world road networks with up to almost 160,000 nodes.


title: Defining Concepts of Emotion: From Philosophy to Science

abstract:
  This paper is motivated by a series of (related) questions as to whether a
computer can have pleasure and pain, what pleasure (and intensity of pleasure)
is, and, ultimately, what concepts of emotion are.
  To determine what an emotion is, is a matter of conceptualization, namely,
understanding and explicitly encoding the concept of emotion as people use it
in everyday life. This is a notoriously difficult problem (Frijda, 1986, Fehr
\& Russell, 1984). This paper firstly shows why this is a difficult problem by
aligning it with the conceptualization of a few other so called semantic
primitives such as "EXIST", "FORCE", "BIG" (plus "LIMIT"). The definitions of
these thought-to-be-indefinable concepts, given in this paper, show what formal
definitions of concepts look like and how concepts are constructed. As a
by-product, owing to the explicit account of the meaning of "exist", the famous
dispute between Einstein and Bohr is naturally resolved from linguistic point
of view. Secondly, defending Frijda's view that emotion is action tendency (or
Ryle's behavioral disposition (propensity)), we give a list of emotions defined
in terms of action tendency. In particular, the definitions of pleasure and the
feeling of beauty are presented.
  Further, we give a formal definition of "action tendency", from which the
concept of "intensity" of emotions (including pleasure) is naturally derived in
a formal fashion. The meanings of "wish", "wait", "good", "hot" are analyzed.


title: Operads of finite posets

abstract:
  We describe four natural operad structures on the vector space generated by
isomorphism classes of finite posets. The three last ones are set-theoretical
and can be seen as a simplified version of the first, the same way the NAP
operad behaves with respect to the pre-Lie operad. Moreover the two first ones
are isomorphic.


title: On the rank of a product of manifolds

abstract:
  This note gives an example of closed smooth manifolds $M$ and $N$ for which
the rank of $M\times N$ is strictly greater than $rank M + rank N$.


title: Topological phases protected by point group symmetry

abstract:
  We consider symmetry protected topological (SPT) phases with crystalline
point group symmetry, dubbed point group SPT (pgSPT) phases. We show that such
phases can be understood in terms of lower-dimensional topological phases with
on-site symmetry, and can be constructed as stacks and arrays of these
lower-dimensional states. This provides the basis for a general framework to
classify and characterize bosonic and fermionic pgSPT phases, that can be
applied for arbitrary crystalline point group symmetry and in arbitrary spatial
dimension. We develop and illustrate this framework by means of a few examples,
focusing on three-dimensional states. We classify bosonic pgSPT phases and
fermionic topological crystalline superconductors with $Z_2^P$ (reflection)
symmetry, electronic topological crystalline insulators (TCIs) with ${\rm U}(1)
\times {Z}_2^P$ symmetry, and bosonic pgSPT phases with $C_{2v}$ symmetry,
which is generated by two perpendicular mirror reflections. We also study
surface properties, with a focus on gapped, topologically ordered surface
states. For electronic TCIs we find a $Z_8 \times Z_2$ classification, where
the $Z_8$ corresponds to known states obtained from non-interacting electrons,
and the $Z_2$ corresponds to a "strongly correlated" TCI that requires strong
interactions in the bulk. Our approach may also point the way toward a general
theory of symmetry enriched topological (SET) phases with crystalline point
group symmetry.


title: On the topological type of a set of plane valuations with symmetries

abstract:
  Let $\{C_i : i=1,\ldots,r\}$ be a set of irreducible plane curve
singularities. For an action of a finite group $G$, let $\Delta^{L}(\{t_{a
i}\})$ be the Alexander polynomial in $r\vert G\vert$ variables of the
algebraic link $(\bigcup\limits_{i=1}^{r}\bigcup\limits_{a\in G}a C_i )\cap
S^3_{\varepsilon}$ and let $\zeta(t_1,\ldots, t_r) =
\Delta^{L}(t_1,\ldots,t_1,t_2,\ldots,t_2, \ldots,t_r,\ldots,t_r)$ with $\vert
G\vert$ identical variables in each group. (If $r=1$, $\zeta(t)$ is the
monodromy zeta function of the function germ $\prod\limits_{a\in G} a^*f$,
where $f=0$ is an equation defining the curve $C_1$.) We prove that
$\zeta(t_1,\ldots, t_r)$ determines the topological type of the link $L$. We
prove an analogous statement for plane divisorial valuations formulated in
terms of the Poincar\'e series of a set of valuations.


title: Classifying Options for Deep Reinforcement Learning

abstract:
  In this paper we combine one method for hierarchical reinforcement learning -
the options framework - with deep Q-networks (DQNs) through the use of
different "option heads" on the policy network, and a supervisory network for
choosing between the different options. We utilise our setup to investigate the
effects of architectural constraints in subtasks with positive and negative
transfer, across a range of network capacities. We empirically show that our
augmented DQN has lower sample complexity when simultaneously learning subtasks
with negative transfer, without degrading performance when learning subtasks
with positive transfer.


title: False capacitance of supercapacitors

abstract:
  Capacitance measurements from cyclic voltammetry, galvanostatic
chronopotentiometry and calculation of capacitance from imaginary part of
impedance are widely used in investigations of supercapacitors. The methods
assume the supercapacitor is a capacitor, while real objects correspond to
different equivalent electric circuits and show various contributions of
non-capacitive currents to the current which is used for calculation of
capacitance. Specific capacitances which are presented in F g-1 units in
publications not always refer to electric capacitance. The inadequateness of
the capacitance characterization has already resulted in groundless attribution
to supercapacitors of various systems with electrochemical responses of poorly
reversible electrochemical reactions. The number of publications that present
false capacitances is terrible and still increases. A widespread neglect of
energy dissipation in calculations of specific capacitance leads to further
confusion in the characterization of supercapacitors.


title: On Implementing Real-time Specification Patterns Using Observers

abstract:
  English language requirements are often used to specify the behavior of
complex cyber-physical systems. The process of transforming these requirements
to a formal specification language is often challenging, especially if the
specification language does not contain constructs analogous to those used in
the original requirements. For example, requirements often contain real-time
constraints, but many specification languages for model checkers have discrete
time semantics. Work in specification patterns helps to bridge these gaps,
allowing straightforward expression of common requirements patterns in formal
languages. In this work we demonstrate how we support real-time specification
patterns in the Assume Guarantee Reasoning Environment (AGREE) using observers.
We demonstrate that there are subtle challenges, not mentioned in previous
literature, to express real-time patterns accurately using observers. We then
demonstrate that these patterns are sufficient to model real-time requirements
for a real-world avionics system.


title: Bayesian analysis of inflationary features in Planck and SDSS data

abstract:
  We perform a Bayesian analysis to study possible features in the primordial
inflationary power spectrum of scalar perturbations. In particular, we analyse
the possibility of detecting the imprint of these primordial features in the
anisotropy temperature power spectrum of the Cosmic Microwave Background (CMB)
and also in the matter power spectrum P (k). We use the most recent CMB data
provided by the Planck Collaboration and P (k) measurements from the eleventh
data release of the Sloan Digital Sky Survey. We focus our analysis on a class
of potentials whose features are localised at different intervals of angular
scales, corresponding to multipoles in the ranges 10 < l < 60 (Oscill-1) and
150 < l < 300 (Oscill-2). Our results show that one of the step-potentials
(Oscill-1) provides a better fit to the CMB data than does the featureless LCDM
scenario, with a moderate Bayesian evidence in favor of the former. Adding the
P (k) data to the analysis weakens the evidence of the Oscill-1 potential
relative to the standard model and strengthens the evidence of this latter
scenario with respect to the Oscill-2 model.


title:
Astrometric Monitoring of the HR 8799 Planets: Orbit Constraints from
  Self-Consistent Measurements

abstract:
  We present new astrometric measurements from our ongoing monitoring campaign
of the HR 8799 directly imaged planetary system. These new data points were
obtained with NIRC2 on the W.M. Keck II 10 meter telescope between 2009 and
2014. In addition, we present updated astrometry from previously published
observations in 2007 and 2008. All data were reduced using the SOSIE algorithm,
which accounts for systematic biases present in previously published
observations. This allows us to construct a self-consistent data set derived
entirely from NIRC2 data alone. From this dataset, we detect acceleration for
two of the planets (HR 8799b and e) at $>$3$\sigma$. We also assess possible
orbital parameters for each of the four planets independently. We find no
statistically significant difference in the allowed inclinations of the
planets. Fitting the astrometry while forcing coplanarity also returns $\chi^2$
consistent to within 1$\sigma$ of the best fit values, suggesting that if
inclination offsets of $\lesssim$20$^{o}$ are present, they are not detectable
with current data. Our orbital fits also favor low eccentricities, consistent
with predictions from dynamical modeling. We also find period distributions
consistent to within 1$\sigma$ with a 1:2:4:8 resonance between all planets.
This analysis demonstrates the importance of minimizing astrometric systematics
when fitting for solutions to highly undersampled orbits.


title: Classifying (almost)-Belyi maps with Five Exceptional Points

abstract:
  We classify all rational functions whose branching pattern above {0, 1,
infinity} satisfy a certain regularity condition with precisely d=5 exceptions.
This work is motivated by solving second order linear differential equations,
with d=5 true singularities, in terms of hypergeometric functions. A similar
problem was solved for d=4 by Vidunas and Filipuk.


title:
Fujiwhara interaction of tropical cyclone scale vortices using a
  weighted residual collocation method

abstract:
  The fundamental interaction between tropical cyclones was investigated
through a series of water tank experiements by Fujiwhara [20, 21, 22]. However,
a complete understanding of tropical cyclones remains an open research
challenge although there have been numerous investigations through measurments
with aircrafts/satellites, as well as with numerical simulations. This article
presents a computational model for simulating the interaction between cyclones.
The proposed numerical method is presented briefly, where the time integration
is performed by projecting the discrete system onto a Krylov subspace. The
method filters the large scale fluid dynamics using a multiresolution
approximation, and the unresolved dynamics is modeled with a Smagorinsky type
subgrid scale parameterization scheme. Numerical experiments with Fujiwhara
interactions are considered to verify modeling accuracy. An excellent agreement
between the present simulation and a reference simulation at Re = 5000 has been
demonstrated. At Re = 37440, the kinetic energy of cyclones is seen
consolidated into larger scales with concurrent enstrophy cascade, suggesting a
steady increase of energy containing scales, a phenomena that is typical in
two-dimensional turbulence theory. The primary results of this article suggest
a novel avenue for addressing some of the computational challenges of mesoscale
atmospheric circulations.


title: Robust chimera states in SQUID metamaterials with local interactions

abstract:
  We report on the emergence of robust multi-clustered chimera states in a
dissipative-driven system of symmetrically and locally coupled identical SQUID
oscillators. The "snake-like" resonance curve of the single SQUID
(Superconducting QUantum Interference Device) is the key to the formation of
the chimera states and is responsible for the extreme multistability exhibited
by the coupled system that leads to attractor crowding at the geometrical
resonance (inductive-capacitive) frequency. Until now, chimera states were
mostly believed to exist for nonlocal coupling. Our findings provide
theoretical evidence that nearest neighbor interactions are indeed capable of
supporting such states in a wide parameter range. SQUID metamaterials are the
subject of intense experimental investigations and we are highly confident that
the complex dynamics demonstrated in this manuscript can be confirmed in the
laboratory.


title:
Atomic Read/Write Memory in Signature-free Byzantine Asynchronous
  Message-passing Systems

abstract:
  This article presents a signature-free distributed algorithm which builds an
atomic read/write shared memory on top of an $n$-process asynchronous
message-passing system in which up to $t<n/3$ processes may commit Byzantine
failures. From a conceptual point of view, this algorithm is designed to be as
close as possible to the algorithm proposed by Attiya, Bar-Noy and Dolev (JACM
1995), which builds an atomic register in an $n$-process asynchronous
message-passing system where up to $t<n/2$ processes may crash. The proposed
algorithm is particularly simple. It does not use cryptography to cope with
Byzantine processes, and is optimal from a $t$-resilience point of view
($t<n/3$). A read operation requires $O(n)$ messages, and a write operation
requires $O(n^2)$ messages.


title: P-type polar transition of chemically doped multilayer MoS2 transistor

abstract:
  The accessibility of both n-type and p-type MoS2 FET is necessary for
complementary device applications involving MoS2. However, MoS2 PFET is rarely
achieved due to pinning effect resulting high Rc at metal-MoS2 interface and
the inherently strong n-type property of the MoS2 material. In this study, we
realized a high-performance multi-layer MoS2 PFET via controllable chemical
doping, which has an excellent on/off ratio of 107 and a maximum hole mobility
of 72 cm2/Vs at room temperature, and these values are further exceeding to 109
and 132 cm2/Vs at 133K. In addition, we revealed that large Rc hindered the
polar transition of MoS2 FET from n-type to p-type, meanwhile channel Rs
limited Ion of PFET. Therefore it is suggested that reducing Rc at high work
function metal-MoS2 interface and p-type doping of channel were necessary for
achieving high performance MoS2 PFET. Based on the high performance PFET, we
successfully demonstrated a MoS2 CMOS inverter by integrating NFET and PFET.


title:
Scrape-off layer turbulence in TCV: evidence in support of stochastic
  modelling

abstract:
  Intermittent fluctuations in the TCV scrape-off layer have been investigated
by analysing long Langmuir probe data time series under stationary conditions,
allowing calculation of fluctuation statistics with high accuracy. The ion
saturation current signal is dominated by the frequent occurrence of
large-amplitude bursts attributed to filament structures moving through the
scrape-off layer. The average burst shape is well described by a
double-exponential wave-form with constant duration, while the waiting times
and peak amplitudes of the bursts both have an exponential distribution.
Associated with bursts in the ion saturation current is a dipole shaped
floating potential structure and radially outwards directed electric drift
velocity and particle flux, with average peak values increasing with the
saturation current burst amplitude. The floating potential fluctuations have a
normal probability density function while the distributions for the ion
saturation current and estimated radial velocity have exponential tails for
large fluctuations. These findings are discussed in the light of prevailing
theories for filament motion and a stochastic model for intermittent scrape-off
layer plasma fluctuations.


title: Understanding Human-Centric Images: From Geometry to Fashion

abstract:
  Understanding humans from photographs has always been a fundamental goal of
computer vision. In this thesis we have developed a hierarchy of tools that
cover a wide range of topics with the objective of understanding humans from
monocular RGB image: from low level feature point descriptors to high level
fashion-aware conditional random fields models. In order to build these high
level models it is paramount to have a battery of robust and reliable low and
mid level cues. Along these lines, we have proposed two low-level keypoint
descriptors: one based on the theory of the heat diffusion on images, and the
other that uses a convolutional neural network to learn discriminative image
patch representations. We also introduce distinct low-level generative models
for representing human pose: in particular we present a discrete model based on
a directed acyclic graph and a continuous model that consists of poses
clustered on a Riemannian manifold. As mid level cues we propose two 3D human
pose estimation algorithms: one that estimates the 3D pose given a noisy 2D
estimation, and an approach that simultaneously estimates both the 2D and 3D
pose. Finally, we formulate higher level models built upon low and mid level
cues for understanding humans from single images. Concretely, we focus on two
different tasks in the context of fashion: semantic segmentation of clothing,
and predicting the fashionability from images with metadata to ultimately
provide fashion advice to the user. For all presented approaches we present
extensive results and comparisons against the state-of-the-art and show
significant improvements on the entire variety of tasks we tackle.


title:
Numerical solution of the quantum Lenard-Balescu equation for a
  one-component plasma

abstract:
  We present a numerical solution of the quantum Lenard-Balescu equation using
a spectral method, namely an expansion in Laguerre polynomials. This method
exactly conserves both particles and energy and facilitates the integration
over the dielectric function. To demonstrate the method, we solve the
equilibration problem for a spatially homogeneous one-component plasma with
various initial conditions. Unlike the more usual Landau/Fokker-Planck system,
this method requires no input Coulomb logarithm; the logarithmic terms in the
collision integral arise naturally from the equation along with the
non-logarithmic order-unity terms. The spectral method can also be used to
solve the Landau equation and a quantum version of the Landau equation in which
the integration over the wavenumber requires only a lower cutoff. We solve
these problems as well and compare them with the full Lenard-Balescu solution
in the weak-coupling limit. Finally, we discuss the possible generalization of
this method to include spatial inhomogeneity and velocity anisotropy.


title:
The Hausdorff and dynamical dimensions of self-affine sponges: a
  dimension gap result

abstract:
  We construct a self-affine sponge in $\mathbb R^3$ whose dynamical dimension,
i.e. the supremum of the Hausdorff dimensions of its invariant measures, is
strictly less than its Hausdorff dimension. This resolves a long-standing open
problem in the dimension theory of dynamical systems, namely whether every
expanding repeller has an ergodic invariant measure of full Hausdorff
dimension. More generally we compute the Hausdorff and dynamical dimensions of
a large class of self-affine sponges, a problem that previous techniques could
only solve in two dimensions. The Hausdorff and dynamical dimensions depend
continuously on the iterated function system defining the sponge, implying that
sponges with a dimension gap represent a nonempty open subset of the parameter
space.


title: Compact Perturbative Expressions For Neutrino Oscillations in Matter

abstract:
  We further develop and extend a recent perturbative framework for neutrino
oscillations in uniform matter density so that the resulting oscillation
probabilities are accurate for the complete matter potential versus baseline
divided by neutrino energy plane. This extension also gives the exact
oscillation probabilities in vacuum for all values of baseline divided by
neutrino energy. The expansion parameter used is related to the ratio of the
solar to the atmospheric $\Delta m^2$ scales but with a unique choice of the
atmospheric $\Delta m^2$ such that certain first-order effects are taken into
account in the zeroth-order Hamiltonian. Using a mixing matrix formulation,
this framework has the exceptional feature that the neutrino oscillation
probability in matter has the same structure as in vacuum, to all orders in the
expansion parameter. It also contains all orders in the matter potential and
$\sin\theta_{13}$. It facilitates immediate physical interpretation of the
analytic results, and makes the expressions for the neutrino oscillation
probabilities extremely compact and very accurate even at zeroth order in our
perturbative expansion. The first and second order results are also given which
improve the precision by approximately two or more orders of magnitude per
perturbative order.


title: A "Social Bitcoin" could sustain a democratic digital world

abstract:
  A multidimensional financial system could provide benefits for individuals,
companies, and states. Instead of top-down control, which is destined to
eventually fail in a hyperconnected world, a bottom-up creation of value can
unleash creative potential and drive innovations. Multiple currency dimensions
can represent different externalities and thus enable the design of incentives
and feedback mechanisms that foster the ability of complex dynamical systems to
self-organize and lead to a more resilient society and sustainable economy.
Modern information and communication technologies play a crucial role in this
process, as Web 2.0 and online social networks promote cooperation and
collaboration on unprecedented scales. Within this contribution, we discuss how
one dimension of a multidimensional currency system could represent
socio-digital capital (Social Bitcoins) that can be generated in a bottom-up
way by individuals who perform search and navigation tasks in a future version
of the digital world. The incentive to mine Social Bitcoins could sustain
digital diversity, which mitigates the risk of totalitarian control by powerful
monopolies of information and can create new business opportunities needed in
times where a large fraction of current jobs is estimated to disappear due to
computerisation.


title:
Eulerian and modified Lagrangian approaches to multi-dimensional
  condensation and collection

abstract:
  Turbulence is argued to play a crucial role in cloud droplet growth. The
combined problem of turbulence and cloud droplet growth is numerically
challenging. Here, an Eulerian scheme based on the Smoluchowski equation is
compared with two Lagrangian superparticle (or su- perdroplet) schemes in the
presence of condensation and collection. The growth processes are studied
either separately or in combination using either two-dimensional turbulence, a
steady flow, or just gravitational acceleration without gas flow. Good
agreement between the differ- ent schemes for the time evolution of the size
spectra is observed in the presence of gravity or turbulence. Higher moments of
the size spectra are found to be a useful tool to characterize the growth of
the largest drops through collection. Remarkably, the tails of the size spectra
are reasonably well described by a gamma distribution in cases with gravity or
turbulence. The Lagrangian schemes are generally found to be superior over the
Eulerian one in terms of computational performance. However, it is shown that
the use of interpolation schemes such as the cloud-in-cell algorithm is
detrimental in connection with superparticle or superdroplet approaches.
Furthermore, the use of symmetric over asymmetric collection schemes is shown
to reduce the amount of scatter in the results.


title:
Kea: a new tool to obtain stellar parameters from low to moderate
  signal/noise and high-resolution Echelle spectra

abstract:
  In this paper we describe Kea a new spectroscopic fitting method to derive
stellar parameters from moderate to low signal/noise, high-resolution spectra.
We developed this new tool to analyze the massive data set of the Kepler
mission reconnaissance spectra that we have obtained at McDonald Observatory.
We use Kea to determine effective temperatures (T_eff), metallicity ([Fe/H]),
surface gravity (log g) and projected rotational velocity (v sin i). Kea
compares the observations to a large library of synthetic spectra that covers a
wide range of different T_eff, [Fe/H] and log g values. We calibrated Kea on
observations of well-characterized standard stars (the Kepler field "platinum"
sample) which range in T_eff from 5000 to 6500 K, in [Fe/H] from -0.5 to +0.4
dex and in log g from 3.2 to 4.6 dex. We then compared the Kea results from
reconnaissance spectra of 45 KOIs (Kepler Object of Interest) to stellar
parameters derived from higher signal/noise spectra obtained with Keck/HIRES.
We find typical uncertainties of 100 K in T_eff, 0.12 dex in [Fe/H] and 0.18
dex in log g.


title:
Adaptive Influence Maximization in Social Networks: Why Commit when You
  can Adapt?

abstract:
  Most previous work on influence maximization in social networks is limited to
the non-adaptive setting in which the marketer is supposed to select all of the
seed users, to give free samples or discounts to, up front. A disadvantage of
this setting is that the marketer is forced to select all the seeds based
solely on a diffusion model. If some of the selected seeds do not perform well,
there is no opportunity to course-correct. A more practical setting is the
adaptive setting in which the marketer initially selects a batch of users and
observes how well seeding those users leads to a diffusion of product
adoptions. Based on this market feedback, she formulates a policy for choosing
the remaining seeds. In this paper, we study adaptive offline strategies for
two problems: (a) MAXSPREAD -- given a budget on number of seeds and a time
horizon, maximize the spread of influence and (b) MINTSS -- given a time
horizon and an expected number of target users to be influenced, minimize the
number of seeds that will be required. In particular, we present theoretical
bounds and empirical results for an adaptive strategy and quantify its
practical benefit over the non-adaptive strategy. We evaluate adaptive and
non-adaptive policies on three real data sets. We conclude that while benefit
of going adaptive for the MAXSPREAD problem is modest, adaptive policies lead
to significant savings for the MINTSS problem.


title:
The Effects of Turbulence on Three-Dimensional Magnetic Reconnection at
  the Magnetopause

abstract:
  Two- and three-dimensional particle-in-cell simulations of a recent encounter
of the Magnetospheric Multiscale Mission (MMS) with an electron diffusion
region at the magnetopause are presented. While the two-dimensional simulation
is laminar, turbulence develops at both the x-line and along the magnetic
separatrices in the three-dimensional simulation. The turbulence is strong
enough to make the magnetic field around the reconnection island chaotic and
produces both anomalous resistivity and anomalous viscosity. Each contribute
significantly to breaking the frozen-in condition in the electron diffusion
region. A surprise is that the crescent-shaped features in velocity space seen
both in MMS observations and in two-dimensional simulations survive, even in
the turbulent environment of the three-dimensional system. This suggests that
MMS's measurements of crescent distributions do not exclude the possibility
that turbulence plays an important role in magnetopause reconnection.


title:
One year in the Earth's magnetosphere: A global MHD simulation and
  spacecraft measurements

abstract:
  The response of the Earth's magnetosphere to changing solar wind conditions
are studied with a 3D Magnetohydrodynamic (MHD) model. One full year (155
Cluster orbits) of the Earth's magnetosphere is simulated using Grand Unified
Magnetosphere Ionosphere Coupling simulation (GUMICS-4) magnetohydrodynamic
code. Real solar wind measurements are given to the code as input to create the
longest lasting global magnetohydrodynamics simulation to date. The
applicability of the results of the simulation depends critically on the input
parameters used in the model. Therefore, the validity and the variance of the
OMNIWeb data is first investigated thoroughly using Cluster measurement close
to the bow shock. The OMNIWeb and the Cluster data were found to correlate very
well before the bow shock. The solar wind magnetic field and plasma parameters
are not changed significantly from the $L_1$ Lagrange point to the foreshock,
therefore the OMNIWeb data is appropriate input to the GUMICS-4. The Cluster
SC3 footprints are determined by magnetic field mapping from the simulation
results and the Tsyganenko (T96) model in order to compare two methods. The
determined footprints are in rather good agreement with the T96. However, it
was found that the footprints agree better in the northern hemisphere than the
southern one during quiet conditions. If the By is not zero, the agreement of
the GUMICS-4 and T96 footprint is worse in longitude in the southern
hemisphere. Overall, the study implies that a 3D MHD model can increase our
insight of the response of the magnetosphere to solar wind conditions.


title:
Quark-hadron phase structure, thermodynamics and magnetization of QCD
  matter

abstract:
  SU($3$) Polyakov linear-sigma model (PLSM) is systematically implemented to
characterize the quark-hadron phase structure and to determine various
thermodynamic quantities and magnetization of the QCD matter. In mean-field
approximation, the dependence of the chiral order-parameter on finite magnetic
field is also calculated. In a wide range of temperatures and magnetic field
strengths, various thermodynamic quantities including trace anomaly, speed of
sound squared, entropy density, specific heat are presented and some magnetic
properties are described, as well. Wherever available these results are
confronted to recent lattice QCD calculations. The temperature dependence of
these quantities confirms our previous result that the transition temperature
is reduced with the increase in the magnetic field strength, i.e. QCD matter is
to be characterized by an inverse magnetic catalysis. Furthermore, the
temperature dependence of the magnetization shows that the conclusion that the
QCD matter has paramagnetic properties slightly below and far above the
pseudo-critical temperature, is confirmed, as well. The excellent agreement
with recent lattice calculations proves that our QCD-like approach (PLSM) seems
to possess the correct degrees-of-freedom in both hadronic and partonic phases
and describes well the dynamics deriving confined hadrons to deconfined
quark-gluon plasma.


title:
Existence and Stability of Positive Periodic Solutions to Functional
  Differential Equations

abstract:
  We establish several delay-independent criteria for the existence and
stability of positive periodic solutions of n-dimensional nonautonomous
functional differential equation by several fixed point theorems. Examples from
positive and negative growth feedback systems demonstrate the results.


title:
Analytic and nearly optimal self-testing bounds for the
  Clauser-Horne-Shimony-Holt and Mermin inequalities

abstract:
  Self-testing refers to the phenomenon that certain extremal quantum
correlations (almost) uniquely identify the quantum system under consideration.
For instance observing the maximal violation of the CHSH inequality certifies
that the two parties share a singlet. While self-testing results are known for
several classes of states, in many cases they are only applicable if the
observed statistics are almost perfect, which makes them unsuitable for
practical applications. Practically relevant self-testing bounds are much less
common and moreover they all result from a single numerical method (with one
exception which we discuss in detail). In this work we present a new technique
for proving analytic self-testing bounds of practically relevant robustness. We
obtain improved bounds for the case of self-testing the singlet using the CHSH
inequality (in particular we show that non-trivial fidelity with the singlet
can be achieved as long as the violation exceeds $\beta^{*} = (16 + 14
\sqrt{2})/17 \approx 2.11$). In case of self-testing the tripartite GHZ state
using the Mermin inequality we derive a bound which not only improves on
previously known results but turns out to be tight. We discuss other scenarios
to which our technique can be immediately applied.


title:
OSSOS III - Resonant Trans-Neptunian Populations: Constraints from the
  first quarter of the Outer Solar System Origins Survey

abstract:
  The first two observational sky "blocks" of the Outer Solar System Origins
Survey (OSSOS) have significantly increased the number of well-characterized
observed trans-Neptunian objects (TNOs) in Neptune's mean motion resonances. We
describe the 31 securely resonant TNOs detected by OSSOS so far, and we use
them to independently verify the resonant population models from the
Canada-France Ecliptic Plane Survey (CFEPS; Gladman et al. 2012), with which we
find broad agreement. We confirm that the 5:2 resonance is more populated than
models of the outer Solar System's dynamical history predict; our minimum
population estimate shows that the high eccentricity (e>0.35) portion of the
resonance is at least as populous as the 2:1 and possibly as populated as the
3:2 resonance. One OSSOS block was well-suited to detecting objects trapped at
low libration amplitudes in Neptune's 3:2 resonance, a population of interest
in testing the origins of resonant TNOs. We detected three 3:2 objects with
libration amplitudes below the cutoff modeled by CFEPS; OSSOS thus offers new
constraints on this distribution. The OSSOS detections confirm that the 2:1
resonance has a dynamically colder inclination distribution than either the 3:2
or 5:2 resonances. Using the combined OSSOS and CFEPS 2:1 detections, we
constrain the fraction of 2:1 objects in the symmetric mode of libration to be
0.2-0.85; we also constrain the fraction of leading vs. trailing asymmetric
librators, which has been theoretically predicted to vary depending on
Neptune's migration history, to be 0.05-0.8. Future OSSOS blocks will improve
these constraints.


title: Centralized Coded Caching for Heterogeneous Lossy Requests

abstract:
  Centralized coded caching of popular contents is studied for users with
heterogeneous distortion requirements, corresponding to diverse processing and
display capabilities of mobile devices. Users' distortion requirements are
assumed to be fixed and known, while their particular demands are revealed only
after the placement phase. Modeling each file in the database as an independent
and identically distributed Gaussian vector, the minimum delivery rate that can
satisfy any demand combination within the corresponding distortion target is
studied. The optimal delivery rate is characterized for the special case of two
users and two files for any pair of distortion requirements. For the general
setting with multiple users and files, a layered caching and delivery scheme,
which exploits the successive refinability of Gaussian sources, is proposed.
This scheme caches each content in multiple layers, and it is optimized by
solving two subproblems: lossless caching of each layer with heterogeneous
cache capacities, and allocation of available caches among layers. The delivery
rate minimization problem for each layer is solved numerically, while two
schemes, called the proportional cache allocation (PCA) and ordered cache
allocation (OCA), are proposed for cache allocation. These schemes are compared
with each other and the cut-set bound through numerical simulations.


title: Strategic Formation of Heterogeneous Networks

abstract:
  We establish a network formation game for the Internet's Autonomous System
(AS) interconnection topology. The game includes different types of players,
accounting for the heterogeneity of ASs in the Internet. In this network
formation game, the utility of a player depends on the network structure, e.g.,
the distances between nodes and the cost of links. We also consider the case
where utility (or monetary) transfers are allowed between the players. We
incorporate reliability considerations in the player's utility function, and
analyze static properties of the game as well as its dynamic evolution. We
provide dynamic analysis of topological quantities, and explain the prevalence
of some "network motifs" in the Internet graph. We assess our predictions with
real-world data.