  We study algorithmic problems on subsets of Euclidean space of low fractal
dimension. These spaces are the subject of intensive study in various branches
of mathematics, including geometry, topology, and measure theory. There are
several well-studied notions of fractal dimension for sets and measures in
Euclidean space. We consider a definition of fractal dimension for finite
metric spaces which agrees with standard notions used to empirically estimate
the fractal dimension of various sets. We define the fractal dimension of some
metric space to be the infimum $\delta>0$, such that for any $\epsilon > 0$,
for any ball $B$ of radius $r\geq 2\epsilon$, and for any $\epsilon $-net $N$
(that is, for any maximal $\epsilon $-packing), we have $|B\cap
N|=O((r/\epsilon)^\delta)$.
  Using this definition we obtain faster algorithms for a plethora of classical
problems on sets of low fractal dimension in Euclidean space. Our results apply
to exact and fixed-parameter algorithms, approximation schemes, and spanner
constructions. Interestingly, the dependence of the performance of these
algorithms on the fractal dimension nearly matches the currently best-known
dependence on the standard Euclidean dimension. Thus, when the fractal
dimension is strictly smaller than the ambient dimension, our results yield
improved solutions in all of these settings.


  In this paper, we define a semi-symmetric metric Killing vector field, then
study semi-symmetric metric Killing vector fields on warped and multiply warped
products with a semi-symmetric metric connection. We also study Killing and
2-Killing vector fields on multiply warped products.


  The Petrov type I condition for the solutions of vacuum Einstein equations in
both of the non-relativistic and relativistic hydrodynamic expansions is
checked. We show that it holds up to the third order of the non-relativistic
hydrodynamic expansion parameter, but it is violated at the fourth order even
if we choose a general frame. On the other hand, it is found that the condition
holds at least up to the second order of the derivative expansion parameter.
Turn the logic around, through imposing the Petrov type I condition and
Hamiltonian constraint on a finite cutoff surface, we show that the stress
tensor of the relativistic fluid can be recovered with correct first order and
second order transport coefficients dual to the solutions of vacuum Einstein
equations.


  Scalable photonic quantum technologies require on-demand single-photon
sources with simultaneously high levels of purity, indistinguishability, and
efficiency. These key features, however, have only been demonstrated separately
in previous experiments. Here, by s-shell pulsed resonant excitation of a
Purcell-enhanced quantum dot-micropillar system, we deterministically generate
resonance fluorescence single photons which, at pi pulse excitation, have an
extraction efficiency of 66%, single-photon purity of 99.1%, and photon
indistinguishability of 98.5%. Such a single-photon source for the first time
combines the features of high efficiency and near-perfect levels of purity and
indistinguishabilty, and thus open the way to multi-photon experiments with
semiconductor quantum dots.


  The pp-wave (Penrose limit) in conformal field theory can be viewed as a
special contraction of the unitary representations of the conformal group. We
study the kinematics of conformal fields in this limit in a geometric approach
where the effect of the contraction can be visualized as an expansion of
space-time. We discuss the two common models of space-time as carrier spaces
for conformal fields: One is the usual Minkowski space and the other is the
coset of the conformal group over its maximal compact subgroup. We show that
only the latter manifold and the corresponding conformal representation theory
admit a non-singular contraction limit. We also address the issue of
correlation functions of conformal fields in the pp-wave limit. We show that
they have a well-defined contraction limit if their space-time dependence
merges with the dependence on the coordinates of the R symmetry group. This is
a manifestation of the fact that in the limit the space-time and R symmetries
become indistinguishable. Our results might find applications in actual
calculations of correlation functions of composite operators in N=4 super
Yang-Mills theory.


  In the present work we analyze the g-essence model for the particular
Lagrangian: $L=R+2[\alpha X^n+\epsilon Y-V(\psi,\bar{\psi})]$. The g-essence
models were proposed recently as an alternative and as a generalization to the
scalar k-essence. We have presented the 3 types solutions of the g-essence
model. We reconstructed the corresponding potentials and the dynamics of the
scalar and fermionic fields according the evolution of the scale factor. The
obtained results shows that the g-essence model can describes the decelerated
and accelerated expansion phases of the universe.


  Mott insulators with spin-orbit entangled j=1/2 moments host intriguing
magnetic properties. The j=1/2 wave function requires cubic symmetry, while a
noncubic crystal field mixes j=1/2 and 3/2 character. Spectroscopic studies of
$5d^5$ iridates typically claim noncubic symmetry, e.g., based on a splitting
of the excited j=3/2 quartet. A sizable splitting is particularly puzzling in
antifluorite-type K$_2$IrCl$_6$, a frustrated fcc quantum magnet with global
cubic symmetry. It raises the fundamental question about the stability of j=1/2
moments against magneto-elastic coupling. Combining resonant inelastic x-ray
scattering with optical spectroscopy, we demonstrate that the multi-peak line
shape in K$_2$IrCl$_6$ reflects a vibronic character of the j=3/2 states rather
than a noncubic crystal field. The quasimolecular crystal structure with well
separated IrCl$_6$ octahedra explains the existence of well-defined sidebands
that are usually smeared out in solids. Our results highlight the
spin-orbital-lattice entangled character of cubic K$_2$IrCl$_6$ with ideal
j=1/2 moments.


  Background Despite the benefits offered by an abundance of health
applications promoted on app marketplaces (e.g., Google Play Store), the wide
adoption of mobile health and e-health apps is yet to come. Objective This
study aims to investigate the current landscape of smartphone apps that focus
on improving and sustaining health and wellbeing. Understanding the categories
that popular apps focus on and the relevant features provided to users, which
lead to higher user scores and downloads will offer insights to enable higher
adoption in the general populace. This study on 1,000 mobile health
applications aims to shed light on the reasons why particular apps are liked
and adopted while many are not. Methods User-generated data (i.e. review
scores) and company-generated data (i.e. app descriptions) were collected from
app marketplaces and manually coded and categorized by two researchers. For
analysis, Artificial Neural Networks, Random Forest and Na\"ive Bayes
Artificial Intelligence algorithms were used. Results The analysis led to
features that attracted more download behavior and higher user scores. The
findings suggest that apps that mention a privacy policy or provide videos in
description lead to higher user scores, whereas free apps with in-app purchase
possibilities, social networking and sharing features and feedback mechanisms
lead to higher number of downloads. Moreover, differences in user scores and
the total number of downloads are detected in distinct subcategories of mobile
health apps. Conclusion This study contributes to the current knowledge of
m-health application use by reviewing mobile health applications using content
analysis and machine learning algorithms. The content analysis adds significant
value by providing classification, keywords and factors that influence download
behavior and user scores in a m-health context.


  Designs for quantum error correction depend strongly on the connectivity of
the qubits. For solid state qubits, the most straightforward approach is to
have connectivity constrained to a planar graph. Practical considerations may
also further restrict the connectivity, resulting in a relatively sparse graph
such as the heavy-hex architecture of current IBM Quantum devices. In such
cases it is hard to use all qubits to their full potential. Instead, in order
to emulate the denser connectivity required to implement well-known quantum
error correcting codes, many qubits remain effectively unused. In this work we
show how this bug can be turned into a feature. By using the unused qubits of
one code to execute another, two codes can be implemented on top of each other,
allowing easy application of fault-tolerant entangling gates and measurements.
We demonstrate this by realizing a surface code and a Bacon-Shor code on a 133
qubit IBM Quantum device. Using transversal CX gates and lattice surgery we
demonstrate entanglement between these logical qubits with code distance up to
$d = 4$ and five rounds of stabilizer measurement cycles. The nonplanar
coupling between the qubits allows us to simultaneously measure the logical
$XX$, $YY$, and $ZZ$ observables. With this we verify the violation of Bell's
inequality for both the $d=2$ case with post selection featuring a fidelity of
$94\%$, and the $d=3$ instance using only quantum error correction.


  We study whether the broad enhancement X(1576) arises from the final state
interaction (FSI) of $\rho(1450,1700)\to \rho^+\rho^-\to K^{+}K^{-}$ decays. We
consider both the absorptive and dispersive contribution of the above
amplitudes since the intermediate states are very close to $\rho(1450,1700)$.
The same mechanism leads to a similar enhancement around 1580 MeV in the
$\pi^{+}\pi^-$ spectrum in the $J/\psi\to \pi^{0}\pi^{+}\pi^{-}$ channel, which
can be used to test whether X(1576) can be ascribed to the FSI effect of
$\rho(1450,1700)\to \rho^+\rho^-$.


  In a recent paper [arXiv:2009.00716], Rahman and Shpilrain proposed a new
key-exchange protocol MAKE based on external semidirect product of groups. The
purpose of this paper is to show that the key exchange protocol is insecure. We
were able to break their challenge problem in under a second.


  We study the decay of two repulsively interacting bosons tunneling through a
delta potential barrier by direct numerical solution of the time-dependent
Schr\"odinger equation. The solutions are analyzed according to the regions of
particle presence: both particles inside the trap (in-in), one particle in and
one particle out (in-out), and both particles outside (out-out). It is shown
that the in-in probability is dominated by exponential decay, and its decay
rate is predicted very well from outgoing boundary conditions.
  Up to a certain range of interaction strength the decay of in-out probability
is dominated by the single particle decay mode.
  The decay mechanisms are adequately described by simple models.


  We study genus $g$ hyperelliptic curves with reduced automorphism group $A_5$
and give equations $y^2=f(x)$ for such curves in both cases where $f(x)$ is a
decomposable polynomial in $x^2$ or $x^5$. For any fixed genus the locus of
such curves is a rational variety. We show that for every point in this locus
the field of moduli is a field of definition. Moreover, there exists a rational
model $y^2=F(x)$ or $y^2=x F(x)$ of the curve over its field of moduli where
$F(x)$ can be chosen to be decomposable in $x^2$ or $x^5$. While similar
equations have been given in Bujalance, Cirre, Gamboa and Gromadzki (2001) over
$\mathbb R$, this is the first time that these equations are given over the
field of moduli of the curve.


  A learning environment, the tutor-web (http://tutor-web.net), has been
developed and used for educational research. The system is accessible and free
to use for anyone having access to the Web. It is based on open source software
and the teaching material is licensed under the Creative Commons
Attribution-ShareAlike License. The system has been used for computer-assisted
education in statistics and mathematics. It offers a unique way to structure
and link together teaching material and includes interactive quizzes with the
primary purpose of increasing learning rather than mere evaluation.
  The system was used in a course on basic statistics in the University of
Iceland, spring 2013. A randomized trial was conducted to investigate the
difference in learning between students doing regular homework and students
using the system. The difference between the groups was not found to be
significant.


  Workload characterization is an integral part of performance analysis of high
performance computing (HPC) systems. An understanding of workload properties
sheds light on resource utilization and can be used to inform performance
optimization both at the software and system configuration levels. It can
provide information on how computational science usage modalities are changing
that could potentially aid holistic capacity planning for the wider HPC
ecosystem. Here, we report on the results of a detailed workload analysis of
the portfolio of supercomputers comprising the NSF Innovative HPC program in
order to characterize its past and current workload and look for trends to
understand the nature of how the broad portfolio of computational science
research is being supported and how it is changing over time. The workload
analysis also sought to illustrate a wide variety of usage patterns and
performance requirements for jobs running on these systems. File system
performance, memory utilization and the types of parallelism employed by users
(MPI, threads, etc) were also studied for all systems for which job level
performance data was available.


  We present GLAS: Global-to-Local Autonomy Synthesis, a provably-safe,
automated distributed policy generation for multi-robot motion planning. Our
approach combines the advantage of centralized planning of avoiding local
minima with the advantage of decentralized controllers of scalability and
distributed computation. In particular, our synthesized policies only require
relative state information of nearby neighbors and obstacles, and compute a
provably-safe action. Our approach has three major components: i) we generate
demonstration trajectories using a global planner and extract local
observations from them, ii) we use deep imitation learning to learn a
decentralized policy that can run efficiently online, and iii) we introduce a
novel differentiable safety module to ensure collision-free operation, thereby
allowing for end-to-end policy training. Our numerical experiments demonstrate
that our policies have a 20% higher success rate than optimal reciprocal
collision avoidance, ORCA, across a wide range of robot and obstacle densities.
We demonstrate our method on an aerial swarm, executing the policy on low-end
microcontrollers in real-time.


  Levy processes, which have stationary independent increments, are ideal for
modelling the various types of noise that can arise in communication channels.
If a Levy process admits exponential moments, then there exists a parametric
family of measure changes called Esscher transformations. If the parameter is
replaced with an independent random variable, the true value of which
represents a "message", then under the transformed measure the original Levy
process takes on the character of an "information process". In this paper we
develop a theory of such Levy information processes. The underlying Levy
process, which we call the fiducial process, represents the "noise type". Each
such noise type is capable of carrying a message of a certain specification. A
number of examples are worked out in detail, including information processes of
the Brownian, Poisson, gamma, variance gamma, negative binomial, inverse
Gaussian, and normal inverse Gaussian type. Although in general there is no
additive decomposition of information into signal and noise, one is led
nevertheless for each noise type to a well-defined scheme for signal detection
and enhancement relevant to a variety of practical situations.


  We employ the LSZ reduction formula for Matrix Theory introduced in our
earlier work to compute the t-pole S-matrix for three form-three form
scattering. The result agrees completely with tree level D=11 SUGRA. Taken
together with previous results on graviton-graviton scattering this shows that
Matrix Theory indeed reproduces the bosonic sector of the D=11 SUGRA action
including the Chern-Simons term. Furthermore we provide a detailed account of
our framework along with the technology to compute any Matrix Theory one-loop
t-pole scattering amplitude at vanishing p^- exchange.


  Traditional memory writing operations proceed one bit at a time, where e.g.
an individual magnetic domain is force-flipped by a localized external field.
One way to increase material storage capacity would be to write several bits at
a time in the bulk of the material. However, the manipulation of bits is
commonly done through quasi-static operations. While simple to model, this
method is known to reduce memory capacity. In this paper, we demonstrate how a
reinforcement learning agent can exploit the dynamical response of a simple
multi-bit mechanical system to restore its memory to full capacity. To do so,
we introduce a model framework consisting of a chain of bi-stable springs,
which is manipulated on one end by the external action of the agent. We show
that the agent manages to learn how to reach all available states for three
springs, even though some states are not reachable through adiabatic
manipulation, and that both the training speed and convergence within physical
parameter space are improved using transfer learning techniques. Interestingly,
the agent also points to an optimal design of the system in terms of writing
time. In fact, it appears to learn how to take advantage of the underlying
physics: the control time exhibits a non-monotonic dependence on the internal
dissipation, reaching a minimum at a cross-over shown to verify a mechanically
motivated scaling relation.


  This paper is a sequel to Takahashi et al. (2016), in which the authors
investigated the influences of fluctuations in pre-shock accreting matter on
the linear stability of the standing accretion shock in core-collapse
supernovae (CCSNe). If one understands that this was concerning the effect of
the outer boundary condition for the post-shock accretion flows, the present
paper should be regarded as an investigation on the possible influences of the
inner boundary conditions. More specifically, we impose a time-dependent,
oscillating condition at the inner boundary, having in mind the injection of
acoustic power by an oscillating proto-neutron star. We also consider possible
correlations between the inner and outer boundary conditions as invoked in the
argument for Lepton-number Emission Self-sustained Asymmetry, or LESA. In this
paper, we conduct the linear stability analysis of the standing accretion shock
commonly encountered in CCSNe based on Laplace transform. We find that the
acoustic power enhances the standing accretion shock instability, or SASI,
especially when the luminosity is low. On the other hand, the correlation
between the fluctuations of neutrino luminosity at the neutrino sphere has
little influences on the instability, changing the amplitudes of eigenmodes
only slightly. We further investigate steady solution of perturbation
equations, being motivated by LESA, and conclude that not the difference but
the sum of the fluxes of electron-type neutrinos and anti-neutrino is the key
ingredient to production of the self-sustained steady perturbed configuration.


  We derive an effective field theory (EFT) for cosmological Lyman alpha forest
fluctuations valid for the power spectrum at the one-loop order. The
``bottom-up'' EFT expansion at the level of the transmitted flux is identical
to the line-of-sight dependent bias model first derived by Desjacques et al. We
confirm this result by a ``top-down'' derivation based on the exponential map
of the optical depth field. Specifically, we show that the combination of the
exponential map and conditions of renormalizability generates the same EFT
expansion as the ``bottom-up'' approach. In passing, we point out
inconsistencies of the tree-level perturbative expansion of the exponential map
without counterterms. To facilitate practical applications, we generalize the
FFTLog method for efficient calculations of one-loop integrals from new
line-of-sight dependent operators. Finally, we compare the one-loop EFT model
against data from the Sherwood hydrodynamic simulation. The theory fits the
data with sub percent accuracy up to $k= $ 3 $h$Mpc$^{-1}$ at $z= 2.8$ for both
3D and 1D correlations. Our model can be readily used for cosmological
full-shape analyses of Lyman alpha forest data.


  A methodology for substantially increasing the magnitude of the
electrokinetic streaming potential (Vs) from ~ 0.02 V to as large as ~ 1.6 V is
proposed. This is done through deploying textured, liquid-filled surfaces
(LFS), filled with low viscosity oils, for electrolyte flow. The charge density
at the electrolyte-oil interface as well as the enhanced slip may be
responsible for enhancement of the Vs. It was found, through experimental
analysis as well as computational simulations, that the fluid slip length was
inversely proportional to the filling oil viscosity, and influences the Vs. The
study provides new perspectives related to complex electrolyte flow conditions
as may be relevant for energy harvesting applications.


  We present a geochemical dataset acquired during continual sampling over 7
months (bi-weekly) and 4 weeks (every 8 hours) in the Neuwied Basin, a part of
the East Eifel Volcanic Field (EEVF). We used a combination of geochemical,
geophysical, and statistical methods to identify potential causal processes
underlying the correlations of degassing patterns of four gases (He, Rn, CO2,
O2), earth tides, and tectonic processes in three mineral springs (Nette,
Kaerlich and Kobern). We explored whether temporal relations in gas
concentrations in the three mineral springs could be indicators of hidden
faults through which the gases migrate to the surface from deeper underground.
Our results do not confirm CO2 as a primary carrier gas for trace gases in all
springs. Temporal analyses of the CO2-He couple indicate that Nette and
K\"arlich are directly linked via a continuous tectonic fault in an ENE-WSW
trending direction. There is also evidence that Kaerlich and Kobern (NNE-SSW
fault system) and Nette and Kobern (NW-SE fault system) are tectonically
linked. These fault linkages are unknown previously but could be related to the
rising numbers of earthquake events occurring in this area since 2010. We did
not find any evidence that weather processes (e.g., barometric pressure), earth
tides, or low local earthquake magnitudes actively modulate degassing. The
volcanic activity in the EEVF is dormant but not extinct and to understand and
monitor its magmatic and degassing systems, we recommend bi-weekly samplings at
minimum.


This paper has been withdrawn.


  New applications of Feynman disentangling method in quantum mechanics are
studied and the time-dependent singular oscillator problem is solved in this
approach. The important role of representation group theory is discussed in
this context.


  Searching for topological insulators/superconductors is a central subject in
recent condensed matter physics. As a theoretical aspect, various
classification methods of symmetry-protected topological phases have been
developed, where the topology of a gapped Hamiltonian is investigated from the
viewpoint of its onsite/crystal symmetry. On the other hand, topological
physics also appears in semimetals, whose gapless points can be characterized
by topological invariants. Stimulated by this background, we shed light on the
topology of nodal superconductors. In this paper, we review our modern
topological classification theory of superconducting gap nodes in terms of
symmetry. The classification method elucidates nontrivial gap structures
arising from nonsymmorphic symmetry or angular momentum, which cannot be
predicted by a conventional theory.


  In this paper, we would like to study operator reconstruction in a class of
holographic tensor networks describing renormalization group flows studied in
arXiv:2210.12127. We study examples of 2d bulk holographic tensor networks
constructed from Dijkgraaf-Witten theories and found that for both
$\mathbb{Z}_n$ group and $S_3$ group the number of bulk operators behaving like
a generalized free field in the bulk scales as the order of the group. We also
generalize our study to 3d bulks and found the same scaling for $\mathbb{Z}_n$
theories. However, there is no generalized free field when the bulk comes from
more generic fusion categories such as the Fibonacci model.


  We briefly review the contribution of SN rate measurements to the debate on
SN progenitor scenarios. We find that core collapse rates confirms the rapid
evolution of the star formation rate with redshift. After accounting for the
dispersion of SN Ia measurements and uncertainty of the star formation history,
the standard scenarios for SN Ia progenitors appear consistent with all
observational constraints.


  Strong high-ionization lines such as HeII of young galaxies are puzzling at
high and low redshift. Although recent studies suggest the existence of
non-thermal sources, whether their ionizing spectra can consistently explain
multiple major emission lines remains a question. Here we derive the general
shapes of the ionizing spectra for three local extremely metal-poor galaxies
(EMPGs) that show strong HeII$\lambda$4686. We parameterize the ionizing
spectra composed of a blackbody and power-law radiation mimicking various
stellar and non-thermal sources. We use photoionization models for nebulae, and
determine seven parameters of the ionizing spectra and nebulae by Markov Chain
Monte Carlo methods, carefully avoiding systematics of abundance ratios. We
obtain the general shapes of ionizing spectra explaining $\sim 10$ major
emission lines within observational errors with smooth connections from
observed X-ray and optical continua. We find that an ionizing spectrum of one
EMPG has a blackbody-dominated shape, while the others have convex downward
shapes at $>13.6$ eV, which indicate a diversity of the ionizing spectrum
shapes. We confirm that the convex downward shapes are fundamentally different
from ordinary stellar spectrum shapes, and that the spectrum shapes of these
galaxies are generally explained by the combination of the stellar and
ultra-luminous X-ray sources. Comparisons with stellar synthesis models suggest
that the diversity of the spectrum shapes arises from differences in the
stellar age. If galaxies at $z\gtrsim 6$ are similar to the EMPGs, high energy
($>54.4$ eV) photons of the non-stellar sources negligibly contribute to cosmic
reionization due to relatively weak radiation.


  Conversion of microwave radiation into the optical range has been predicted
to reach unity quantum efficiency in whispering gallery resonators made from an
optically nonlinear crystal and supporting microwave and optical modes
simultaneously. In this work we theoretically explore and experimentally
demonstrate a resonator geometry that can provide the required phase matching
for such a conversion at any desired frequency in the sub-THz range. We show
that such a ring-shaped resonator not only allows for the phase matching, but
also maximizes the overlap of the interacting fields. As a result,
unity-efficient conversion is expected in a resonator with feasible parameters.


  A number of radio interferometers are currently being planned or constructed
to observe 21 cm emission from reionization. Not only will such measurements
provide a detailed view of that epoch, but, since the 21 cm emission also
traces the distribution of matter in the Universe, this signal can be used to
constrain cosmological parameters at 6 < z < 20. The sensitivity of an
interferometer to the cosmological information in the signal may depend on how
precisely the angular dependence of the 21 cm 3-D power spectrum can be
measured. Utilizing an analytic model for reionization, we quantify all the
effects that break the spherical symmetry of the 3-D 21 cm power spectrum and
produce physically motivated predictions for this power spectrum. We find that
upcoming observatories will be sensitive to the 21 cm signal over a wide range
of scales, from larger than 100 to as small as 1 comoving Mpc. We consider
three methods to measure cosmological parameters from the signal: (1) direct
fitting of the density power spectrum to the signal, (2) using only the
velocity field fluctuations in the signal, (3) looking at the signal at large
enough scales such that all fluctuations trace the density field. With the
foremost method, the first generation of 21 cm observations should moderately
improve existing constraints on cosmological parameters for certain
low-redshift reionization scenarios, and a two year observation with the second
generation interferometer MWA5000 can improve constraints on Omega_w, Omega_m
h^2, Omega_b h^2, Omega_nu, n_s, and alpha_s. If the Universe is substantially
ionized by z = 12 or if spin temperature fluctuations are important, we show
that it will be difficult to place competitive constraints on cosmological
parameters with any of the considered methods.


  From the peak of a gravitational microlensing high-magnification event in the
A component of QSO 2237+0305, which was accurately monitored by the GLITP
collaboration, we derived new information on the nature and size of the optical
V-band and R-band sources in the far quasar. If the microlensing peak is caused
by a microcaustic crossing, we firstly obtained that the standard accretion
disk is a scenario more reliable/feasible than other usual axially symmetric
models. Moreover, the standard scenario fits both the V-band and R-band
observations with reduced chi-square values very close to one. Taking into
account all these results, a standard accretion disk around a supermassive
black hole is a good candidate to be the optical continuum main source in QSO
2237+0305. Secondly, using the standard source model and a robust upper limit
on the transverse galactic velocity, we inferred that 90 per cent of the V-band
and R-band luminosities are emitted from a region with radial size less than
1.2 10^{-2} pc (= 3.7 10^{16} cm, at 2*sigma confidence level).


  A novel artificial intelligence (AI) technique that uses machine learning
(ML) methodologies combines several algorithms, which were developed by
ThetaRay, Inc., is applied to NASA's Transiting Exoplanets Survey Satellite
(TESS) dataset to identify exoplanetary candidates. The AI/ML ThetaRay system
is trained initially with Kepler exoplanetary data and validated with confirmed
exoplanets before its application to TESS data. Existing and new features of
the data, based on various observational parameters, are constructed and used
in the AI/ML analysis by employing semi-supervised and unsupervised machine
learning techniques. By the application of ThetaRay system to 10,803 light
curves of threshold crossing events (TCEs) produced by the TESS mission,
obtained from the Mikulski Archive for Space Telescopes, the algorithm yields
about 50 targets for further analysis, and we uncover three new exoplanetary
candidates by further manual vetting. This study demonstrates for the first
time the successful application of the particular combined multiple AI/ML-based
methodologies to a large astrophysical dataset for rapid automated
classification of TCEs.


  In this paper, we propose some algorithms for the simulation of the
distribution of certain diffusions conditioned on terminal point. We prove that
the conditional distribution is absolutely continuous with respect to the
distribution of another diffusion which is easy for simulation, and the formula
for the density is given explicitly.


  A new density field representation technique called the Bezier skeleton
explicit density (BSED) representation scheme for topology optimization of
stretchable metamaterials under finite deformation is proposed for the first
time. The proposed approach overcomes a key deficiency in existing
density-based optimization methods that typically yield designs that do not
have smooth surfaces but have large number of small intricate features, which
are difficult to manufacture even by additive manufacturing. In the proposed
approach, Bezier curves are utilized to describe the skeleton of the design
being optimized where the description of the entire design is realized by
assigning thickness along the curves. This geometric representation technique
ensures that the optimized design is smooth and concise and can easily be tuned
to be manufacturable by additive manufacturing. In the optimization method, the
density field is described by the Heaviside function defined on the Bezier
curves. Compared to NURBS or B-spline based models, Bezier curves have fewer
control parameters and hence are easier to manipulate for sensitivity
derivation, especially for distance sensitivities. Due to its powerful curve
fitting ability, using Bezier curve to represent density field allows exploring
design space effectively and generating concise structures without any
intricate small features at the borders. Furthermore, this density
representation method is mesh independent and design variables are reduced
significantly so that optimization problem can be solved efficiently using
small-scale optimization algorithms such as sequential quadratic programming.


  In early eighties, Belavin and Drinfeld showed that nonskewsymmetric
classical r-matrices for simple Lie algebras are classified by combinatorial
objects which are now called Belavin-Drinfeld triples. Later the second author
of the present paper generalized this result to the case of dynamical
r-matrices, and showed that they correspond to generalized Belavin-Drinfeld
triples. The dynamical r-matrix corresponding a triple is given by a certain
explicit formula, which works for any symmetrizable Kac-Moody algebra. In
special cases, this formula gives the Felder and the Belavin r-matrix.
  In 1994, Felder associated with every dynamical r-matrix a system of
differential equations called the KZB equations. In the case of the Felder and
Belavin r-matrix, solutions of these equations are known to have a
representation theoretical presentation, as conformal blocks (i.e. traces of
products of intertwining operators between representations of Lie algebras).
  In this paper, we propose such a presentation for ANY dynamical r-matrix
given by the second author's formula. In particular, the paper sheds light on
the Belavin-Drinfeld classical r-matrices of 1984.
  This paper begins a series of papers. In the next paper, joint with
T.Schedler, we will give an explicit quantization of the dynamical r-matrices
for simple Lie algebras (in particular, Belavin-Drinfeld r-matrices), which has
been an open problem for a number of years. In another paper, we plan to
generalize the results of the present paper to quantum groups. This should
yield quantum KZB equations which involve quantum R-matrices obtained by
quantizing the classical r-matrices that appear in this paper.


  The multidimensional knapsack problem (MKP) is an NP-hard combinatorial
optimization problem whose solution is determining a subset of maximum total
profit items that do not violate capacity constraints. Due to its hardness,
large-scale MKP instances are usually a target for metaheuristics, a context in
which effective feasibility maintenance strategies are crucial. In 1998, Chu
and Beasley proposed an effective heuristic repair that is still relevant for
recent metaheuristics. However, due to its deterministic nature, the diversity
of solutions such heuristic provides is insufficient for long runs. As a
result, the search for new solutions ceases after a while. This paper proposes
an efficiency-based randomization strategy for the heuristic repair that
increases the variability of the repaired solutions without deteriorating
quality and improves the overall results.


  We study a notion of total acyclicity for complexes of flat sheaves over a
scheme. It is Zariski-local - i.e. it can be verified on any open affine
covering of the scheme - and it agrees, in their setting, with the notion
studied by Murfet and Salarian for sheaves over a noetherian semi-separated
scheme. As part of the study we recover, and in several cases extend the
validity of, recent theorems on existence of covers and precovers in categories
of sheaves. One consequence is the existence of an adjoint to the inclusion of
these totally acyclic complexes into the homotopy category of complexes of flat
sheaves.


  A triangular plate-bending element with a new multi-resolution analysis (MRA)
is proposed and a novel multiresolution element method is hence presented. The
MRA framework is formulated out of a displacement subspace sequence whose basis
functions are built out of scaling and shifting on the element domain of basic
full node shape function. The basic full node shape function is constructed by
means of extending the shape function triangle domain for a split node at the
zero coordinates to the hexagon area enclosing the zero coordinates. As a
result, a new split-full node notion is presented and a novel rational MRA
concept together with the resolution level (RL) is constituted for the element.
Via practical examples, it is found that the traditional triangular plate
element and method is a mono-resolution one and also a special case of the
proposed element and method. The meshing for the monoresolution plate element
model is based on the empiricism while the RL adjusting for the multiresolution
is laid on the rigorous mathematical basis. The analysis clarity of a plate
structure is actually determined by the RL, not by the mesh. Thus, the accuracy
of a structural analysis is replaced by the clarity, the irrational MRA by the
rational and the mesh model by the RL that is the discretized model by the
integrated. The continuous full node shape function unveils secrets behind
assembling artificially of node-related items in global matrix formation by the
conventional FEM.


  We prove that the ribbon graph polynomial of a graph embedded in an
orientable surface is irreducible if and only if the embedded graph is neither
the disjoint union nor the join of embedded graphs. This result is analogous to
the fact that the Tutte polynomial of a graph is irreducible if and only if the
graph is connected and non-separable.


  Recent experimental and numerical studies of the critical-temperature
exponent $\phi$ for the superfluid-Bose glass universality in three-dimensional
systems report strong violations of the key quantum critical relation,
$\phi=\nu z$, where $z$ and $\nu$ are the dynamic and correlation length
exponents, respectively, and question the fundamental concepts underlying
quantum critical phenomena. Using Monte Carlo simulations of the disordered
Bose-Hubbard model, we demonstrate that previous work on the
superfluid-to-normal fluid transition-temperature dependence on chemical
potential (or magnetic field, in spin systems), $T_c \propto
(\mu-\mu_c)^{\phi}$, was misinterpreting transient behavior on approach to the
fluctuation region with the genuine critical law. When the model parameters are
modified to have a broad quantum critical region, simulations of both quantum
and classical models reveal that the $\phi=\nu z$ law [with $\phi=2.7(2)$,
$z=3$, and $\nu = 0.88(5)$] holds true, resolving the $\phi$-exponent "crisis".


  We show that the public experiment held in Venice by F. Tamburini et al and
reported in (2012 New J. Phys. 14 033001) can be regarded as a particular
implementation of Multiple-Input Multiple-Output (MIMO) communications, hence
bringing no advantages with respect to known techniques. Moreover, we explain
that the use of a 'vortex' mode (orbital angular momentum OAM l = 1) at one of
the transmit antennas is not necessary to encode different channels since only
different patterns -or similarly different pointing angles- of the transmit
antennas are required. Finally, we identify why this MIMO transmission allowed
decoding of two signals despite being line-of-sight. This is due to the large
separation between the receiving antennas, which places the transmit antennas
in the near-field Fresnel region of the receiving 'array'. This strongly limits
the application of this technique in practice, since, for a fixed separation
between receiving antennas, the detectable signal power from any additional
vortex mode decays at least as 1/r^4.


  The propagation of Dyakonov-Tamm (DT) surface waves guided by the planar
interface of two nondissipative materials $A$ and $B$ was investigated
theoretically and numerically, via the corresponding canonical boundary-value
problem. Material $A$ is a homogeneous uniaxial dielectric material whose optic
axis lies at an angle $\chi$ relative to the interface plane. Material $B$ is
an isotropic dielectric material that is periodically nonhomogeneous in the
direction normal to the interface. The special case was considered in which the
propagation matrix for material $A$ is non-diagonalizable because the
corresponding surface wave-named the Dyakonov-Tamm-Voigt (DTV) surface wave-has
unusual localization characteristics. The decay of the DTV surface wave is
given by the product of a linear function and an exponential function of
distance from the interface in material $A$; in contrast, the fields of
conventional DT surface waves decay only exponentially with distance from the
interface. Numerical studies revealed that multiple DT surface waves can exist
for a fixed propagation direction in the interface plane, depending upon the
constitutive parameters of materials $A$ and $B$. When regarded as functions of
the angle of propagation in the interface plane, the multiple DT surface-wave
solutions can be organized as continuous branches. A larger number of DT
solution branches exist when the degree of anisotropy of material $A$ is
greater. If $\chi = 0^\circ$ then a solitary DTV solution exists for a unique
propagation direction on each DT branch solution. If $\chi > 0^\circ$, then no
DTV solutions exist. As the degree of nonhomogeneity of material $B$ decreases,
the number of DT solution branches decreases.


  Scharlemann and Thompson define the width of a 3-manifold M as a notion of
complexity based on the topology of M. Their original definition had the
property that the adjacency relation on handles gave a linear order on handles,
but here we consider a more general definition due to Saito, Scharlemann and
Schultens, in which the adjacency relation on handles may give an arbitrary
graph. We show that for compact hyperbolic 3-manifolds, this is linearly
related to a notion of metric complexity, based on the areas of level sets of
Morse functions to graphs, which we call Gromov area.


  Learning from positive and unlabeled data or PU learning is the setting where
a learner only has access to positive examples and unlabeled data. The
assumption is that the unlabeled data can contain both positive and negative
examples. This setting has attracted increasing interest within the machine
learning literature as this type of data naturally arises in applications such
as medical diagnosis and knowledge base completion. This article provides a
survey of the current state of the art in PU learning. It proposes seven key
research questions that commonly arise in this field and provides a broad
overview of how the field has tried to address them.


  Hybrid stars with a quark phase described by the Nambu$-$Jona-Lasinio model
are studied. The hadron-quark model used to determine the stellar matter
equation of state favors the appearance of quark matter: the coincidence of the
deconfinement and chiral transitions and a low vacuum constituent quark mass.
These two properties are essential to build equations of state that predict
pure quark matter in the center of neutron stars. The effect of
vector-isoscalar and vector-isovector terms is discussed, and it is shown that
the vector-isoscalar terms are necessary to describe 2$M_\odot$ hybrid stars,
and the vector-isovector terms result in larger quark cores and a smaller
deconfinement density.


  Using high sensitivity magneto-optical imaging we find evidence for a jump in
local vortex density associated with a vortex liquid to solid phase transition
just above the lower critical field in a single crystal of Bi2Sr2CaCu2O8. We
find the regions of the sample where the jump in vortex density occurs are
associated with low screening currents. In the field - temperature vortex phase
diagram we identify phase boundaries demarcating a dilute vortex liquid phase
and the vortex solid phase. The phase diagram also identifies a coexistence
regime of the dilute vortex liquid and solid phases and shows the effect of
pinning on the vortex liquid to solid phase transition line. We find the phase
boundary lines can be fitted to the theoretically predicted expression for the
low-field portion of the phase boundary delineating a dilute vortex solid from
a vortex liquid phase. We show that the same theoretical fit can be used to
describe the pinning dependence of the low-field phase boundary lines provided
a dependence of the Lindemann number on pinning strength is considered.


  The thermosynthesis concept, biological free energy gain from thermal
cycling, is combined with the concept of the RNA World. The resulting overall
origin of life model gives new explanations for the emergence of the genetic
code and the ribosome. The first protein named pF1 obtains the energy to
support the RNA world by a thermal variation of F1 ATP synthase's binding
change mechanism. This pF1 is the single translation product during the
emergence of the genetic machinery. During thermal cycling pF1 condenses many
substrates with broad specificity, yielding NTPs and randomly constituted
protein and RNA libraries that contain (self)-replicating RNA. The smallness of
pF1 permits the emergence of the genetic machinery by selection of RNA that
increases the fraction of pF1s in the protein library: (1) a progenitor of rRNA
that concatenates amino acids bound to (2) a chain of 'positional tRNAs' linked
by mutual recognition, yielding a pF1 (or its main motif); this positional tRNA
set gradually evolves to a set of regular tRNAs functioning according to the
genetic code, with concomitant emergence of (3) an mRNA coding for pF1.


  The purpose of the present paper is to investigate a hypergroup arising from
irreducible characters of a compact group G and a closed subgroup of G with
finite index. The convolution of this hypergroup is introduced by inducing
irreducible representations and by restricting irreducible representations. The
method of proof relies on character formulae of induced representations of
compact groups and of Frobenius' reciprocity theorem.


  We ask the question whether entropy accumulates, in the sense that the
operationally relevant total uncertainty about an $n$-partite system $A = (A_1,
\ldots A_n)$ corresponds to the sum of the entropies of its parts $A_i$. The
Asymptotic Equipartition Property implies that this is indeed the case to first
order in $n$, under the assumption that the parts $A_i$ are identical and
independent of each other. Here we show that entropy accumulation occurs more
generally, i.e., without an independence assumption, provided one quantifies
the uncertainty about the individual systems $A_i$ by the von Neumann entropy
of suitably chosen conditional states. The analysis of a large system can hence
be reduced to the study of its parts. This is relevant for applications. In
device-independent cryptography, for instance, the approach yields essentially
optimal security bounds valid for general attacks, as shown by Arnon-Friedman
et al.


  Experimental results are presented on event-by-event net-proton fluctuation
measurements in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV, recorded by
the ALICE detector at the CERN LHC. These measurements have as their ultimate
goal an experimental test of Lattice QCD (LQCD) predictions on second and
higher order cumulants of net-baryon distributions to search for critical
behavior near the QCD phase boundary. Before confronting them with LQCD
predictions, account has to be taken of correlations stemming from baryon
number conservation as well as fluctuations of participating nucleons. Both
effects influence the experimental measurements and are usually not considered
in theoretical calculations. For the first time, it is shown that
event-by-event baryon number conservation leads to subtle long-range
correlations arising from very early interactions in the collisions.


  Starting with the power law for the total number of detected infections, we
propose differential equations describing the effect of momentum epidemic
management. Our 2-phase formula matches very well the curves of the total
numbers of the Covid-19 infections in many countries; the first phase is
described by Bessel functions. It provides projections for the saturation,
assuming that the management is steady. We discuss Austria, Brazil, Germany,
Japan, India, Israel, Italy, the Netherlands, Sweden, Switzerland, UK, and the
USA, including some analysis of the second waves.


  The most interesting words in scientific texts will often be novel or rare.
This presents a challenge for scientific word embedding models to determine
quality embedding vectors for useful terms that are infrequent or newly
emerging. We demonstrate how \gls{lsi} can address this problem by imputing
embeddings for domain-specific words from up-to-date knowledge graphs while
otherwise preserving the original word embedding model. We use the MeSH
knowledge graph to impute embedding vectors for biomedical terminology without
retraining and evaluate the resulting embedding model on a domain-specific
word-pair similarity task. We show that LSI can produce reliable embedding
vectors for rare and OOV terms in the biomedical domain.


  We present ASCA observations of LINERs without broad H$\alpha$ emission in
their optical spectra. The sample of "type 2" LINERs consists of NGC 404, 4111,
4192, 4457, and 4569. We have detected X-ray emission from all the objects
except for NGC 404; among the detected objects are two so-called transition
objects (NGC 4192 and NGC 4569), which have been postulated to be composite
nuclei having both an HII region and a LINER component. The images of NGC 4111
and NGC 4569 in the soft (0.5-2 keV) and hard (2-7 keV) X-ray bands are
extended on scales of several kpc. The X-ray spectra of NGC 4111, NGC 4457 and
NGC 4569 are well fitted by a two-component model that consists of soft thermal
emission with $kT\sim0.65$ keV and a hard component represented by a power law
(photon index $\sim$ 2) or by thermal bremsstrahlung emission ($kT\sim$ several
keV). The extended hard X-rays probably come from discrete sources, while the
soft emission most likely originates from hot gas produced by active star
formation in the host galaxy. We have found no clear evidence for the presence
of active galactic nuclei (AGNs) in the sample. If an AGN component is the
primary ionization source of the optical emission lines, then it must be
heavily obscured with a column density significantly larger than $10^{23}$
cm$^{-2}$. Alternatively, the optical emission could be ionized by a population
of exceptionally hot stars.


  We present an extension of the HTL resummation technique to non-equilibrium
situations, starting from the real time formalism in the Keldysh
representation. As an example we calculate the HTL photon self energy, from
which we derive the resummed photon propagator. This propagator is applied to
the computation of the interaction rate of a hard electron in a non-equilibrium
QED plasma. In particular we show the absence of of pinch singularities in
these quantities. Finally we show that the Ward identities relating the HTL
electron self energy to the HTL electron-photon vertex hold as in equilibrium.


  In this paper we present an efficient model of the neuronal potentials
recorded by a deep brain stimulation microelectrode (DBS MER) in the
subthalamic nucleus. It is shown that a computationally efficient filtered
point process consisting of 10,000 neurons, including extracellular filtering
closely matches recordings from 13 Parkinson's disease patients. The recordings
were compared using their voltage amplitude distributions, power spectral
density estimates and phase synchrony. It was found that interspike interval
times modeled using a Weibull distribution with a shape parameter of 0.8,
slightly non-Poisosnian, gave the best fit of the simulations to patient
recordings. These results indicate that part of the `background activity'
present in an DBS MER can be considered to be a very local field potential due
to the surrounding neuronal activity.Therefore, the statistics of the
interspike interval times modify the structure of the background activity.


  We consider functions $f:B\to\Rset$ that obey tropical analogs of classical
Pl\"ucker relations on minors of a matrix. The most general set $B$ that we
deal with in this paper is of the form $\{x\in \Zset^n\colon 0\le x\le a, m\le
x_1+...+x_n\le m'\}$ (a rectangular integer box ``truncated from below and
above''). We construct a basis for the set $\Tscr$ of tropical Pl\"ucker
functions on $B$, a subset $\Bscr\subseteq B$ such that the restriction map
$\Tscr\to\Rset^\Bscr$ is bijective. Also we characterize, in terms of the
restriction to the basis, the classes of submodular, so-called skew-submodular,
and discrete concave functions in $\Tscr$, discuss a tropical analogue of the
Laurentness property, and present other results.


  We modify the construction of the spectral triple over an algebra of holonomy
loops by introducing additional parameters in form of families of matrices.
These matrices generalize the already constructed Euler-Dirac type operator
over a space of connections. We show that these families of matrices can
naturally be interpreted as parameterizing foliations of 4-manifolds. The
corresponding Euler-Dirac type operators then induce Dirac Hamiltonians
associated to the corresponding foliation, in the previously constructed
semi-classical states.


  Improving the description of the equation of state (EoS) of deuterium-tritium
(DT) has recently been shown to change significantly the gain of an Inertial
Confinement Fusion (ICF) target (Hu et al., PRL 104, 235003 (2010)). We use
here an advanced multi-phase equation of state (EoS), based on ab initio
calculations, to perform a full optimization of the laser pulse shape with
hydrodynamic simulations starting from 19 K in DT ice. The thermonuclear gain
is shown to be a robust estimate over possible uncertainties of the EoS. Two
different target designs are discussed, for shock ignition and self-ignition.
In the first case, the areal density and thermonuclear energy can be recovered
by slightly increasing the laser energy. In the second case, a lower in-flight
adiabat is needed, leading to a significant delay (3ns) in the shock timing of
the implosion.


  We exhibit a one-parameter family of regular supersymmetric solutions of type
IIB theory that interpolates between Klebanov-Strassler (KS) and
Maldacena-Nunez (MN). The solution is obtained by applying the supersymmetry
conditions for SU(3)-structure manifolds to an interpolating ansatz proposed by
Papadopoulos and Tseytlin. Other than at the KS point, the family does not have
a conformally-Ricci-flat metric, neither it has self-dual three-form flux.
Nevertheless, the asymptotic IR and UV are that of KS troughout the family,
except for the extremal value of the interpolating parameter where the UV
solution drastically changes to MN. This one-parameter family of solutions is
interpreted as the dual of the baryonic branch of gauge theory, confirming the
expecation that the KS solution corresponds to a particular symmetric point in
the branch.


  We construct an isomorphism between the preprojective cohomological Hall
algebra of an arbitrary quiver and a positive half of the corresponding
Maulik-Okounkov Yangian, which intertwines the respective actions on the
cohomology of the Nakajima quiver varieties. We use this to prove a conjecture
of Okounkov relating the character of the Maulik-Okounkov Lie algebra to Kac
polynomials.


  A. Renyi \cite{Renyi} made a definition that gives one generalization of
simple normality in the context of $Q$-Cantor series. Similarly, in this paper
we give a definition which generalizes the notion of normality in the context
of $Q$-Cantor series. We will prove a theorem that allows us to concatenate
sequences of digits that have a special property to give us the digits of a
$Q$-normal number for certain $Q$. We will then use this theorem to construct a
Q and a real number $x$ that is $Q$-normal.


  Artist, year and style classification of fine-art paintings are generally
achieved using standard image classification methods, image segmentation, or
more recently, convolutional neural networks (CNNs). This works aims to use
newly developed face recognition methods such as FaceNet that use CNNs to
cluster fine-art paintings using the extracted faces in the paintings, which
are found abundantly. A dataset consisting of over 80,000 paintings from over
1000 artists is chosen, and three separate face recognition and clustering
tasks are performed. The produced clusters are analyzed by the file names of
the paintings and the clusters are named by their majority artist, year range,
and style. The clusters are further analyzed and their performance metrics are
calculated. The study shows promising results as the artist, year, and styles
are clustered with an accuracy of 58.8, 63.7, and 81.3 percent, while the
clusters have an average purity of 63.1, 72.4, and 85.9 percent.


  Measurements of $\psi$ and $\psi'$ production at the CERN SPS are compared to
predictions based on a hadronic model of charmonium suppression. Detailed
information is presented to facilitate comparison to other analyses.
Sensitivity of these conclusions to the model parameters is discussed.


  Following a recent proposal, we delineate a general procedure to classify 5d
SCFTs via compactifications of 6d SCFTs on a circle (possibly with a twist by a
discrete global symmetry). The path from 6d SCFTs to 5d SCFTs can be divided
into two steps. The first step involves computing the Coulomb branch data of
the 5d KK theory obtained by compactifying a 6d SCFT on a circle of finite
radius. The second step involves computing the limit of the KK theory when the
inverse radius along with some other mass parameters is sent to infinity. Under
this RG flow, the KK theory reduces to a 5d SCFT. We illustrate these ideas in
the case of untwisted compactifications of rank one 6d SCFTs that can be
constructed in F-theory without frozen singularities. The data of the
corresponding KK theory can be packaged in the geometry of a Calabi-Yau
threefold that we explicitly compute for every case. The RG flows correspond to
flopping a collection of curves in the threefold and we formulate a concrete
set of criteria which can be used to determine which collection of curves can
induce the relevant RG flows, and, in principle, to determine the Calabi-Yau
geometries describing the endpoints of these flows. We also comment on how to
generalize our results to arbitrary rank.


  Understanding plasma dynamics and nonthermal particle acceleration in 3D
magnetic reconnection has been a long-standing challenge. In this paper, we
explore these problems by performing large-scale fully kinetic simulations of
multi-xline plasmoid reconnection with various parameters in both the weak and
strong guide field regimes. In each regime, we have identified its unique 3D
dynamics that leads to field-line chaos and efficient acceleration, and we have
achieved nonthermal acceleration of both electrons and protons into power-law
spectra. The spectral indices agree well with a simple Fermi acceleration
theory that includes guide field dependence. In the low-guide-field regime, the
flux-rope kink instability governs the 3D dynamics for efficient acceleration.
The weak dependence of the spectra on the ion-to-electron mass ratio and
$\beta$ ($\ll1$) implies that the particles are sufficiently magnetized for
Fermi acceleration in our simulations. While both electrons and protons are
injected at reconnection exhausts, protons are primarily injected by
perpendicular electric fields through Fermi reflections and electrons are
injected by a combination of perpendicular and parallel electric fields. The
magnetic power spectra agree with in-situ magnetotail observations, and the
spectral index may reflect a reconnection-driven size distribution of plasmoids
instead of Goldreich-Sridhar vortex cascade. As the guide field becomes
stronger, the oblique flux ropes of large sizes capture the main 3D dynamics
for efficient acceleration. Intriguingly, the oblique flux ropes can also run
into flux-rope kink instability to drive extra 3D dynamics. This work has broad
implications for 3D reconnection dynamics and particle acceleration in
heliophysics and astrophysics.


  We construct semiglobal singular spacetimes for the Einstein equations
coupled to a massless scalar field. Consistent with the heuristic analysis of
Belinskii, Khalatnikov, Lifshitz or BKL for this system, there are no
oscillations due to the scalar field. (This is much simpler than the
oscillatory BKL heuristics for the Einstein vacuum equations.) Prior results
are due to Andersson and Rendall in the real analytic case, and Rodnianski and
Speck in the smooth near-spatially-flat-FLRW case. Similar to Andersson and
Rendall we give asymptotic data at the singularity, which we refer to as final
data, but our construction is not limited to real analytic solutions. This
paper is a test application of tools (a graded Lie algebra formulation of the
Einstein equations and a filtration) intended for the more subtle vacuum case.
We use homological algebra tools to construct a formal series solution, then
symmetric hyperbolic energy estimates to construct a true solution
well-approximated by truncations of the formal one. We conjecture that the
image of the map from final data to initial data is an open set of anisotropic
initial data.


  A numerical algorithm for mean curvature flow of closed mean convex surfaces
with surgery is proposed. The method uses a finite element based mean curvature
flow algorithm based on a coupled partial differential equation system which
directly provides an approximation for mean curvature and outward unit normal.
The proposed numerical surgery process closely follows the analytical surgery
of Huisken \& Sinestrari, and Brendle \& Huisken. The numerical surgery
approach is described in detail, along with extensions to other geometric flows
and methods. Numerical experiments report on the performance of the numerical
surgery process.


  Roman logarithmic binomial formula analogue has been found . It is presented
here also for the case of fibonomial coefficients which recently have been
given a combinatorial interpretation by the present author.


  We present the first three-frequency South Pole Telescope (SPT) cosmic
microwave background (CMB) power spectra. The band powers presented here cover
angular scales 2000 < ell < 9400 in frequency bands centered at 95, 150, and
220 GHz. At these frequencies and angular scales, a combination of the primary
CMB anisotropy, thermal and kinetic Sunyaev-Zel'dovich (SZ) effects, radio
galaxies, and cosmic infrared background (CIB) contributes to the signal. We
combine Planck and SPT data at 220 GHz to constrain the amplitude and shape of
the CIB power spectrum and find strong evidence for non-linear clustering. We
explore the SZ results using a variety of cosmological models for the CMB and
CIB anisotropies and find them to be robust with one exception: allowing for
spatial correlations between the thermal SZ effect and CIB significantly
degrades the SZ constraints. Neglecting this potential correlation, we find the
thermal SZ power at 150 GHz and ell = 3000 to be 3.65 +/- 0.69 muK^2, and set
an upper limit on the kinetic SZ power to be less than 2.8 muK^2 at 95%
confidence. When a correlation between the thermal SZ and CIB is allowed, we
constrain a linear combination of thermal and kinetic SZ power: D_{3000}^{tSZ}
+ 0.5 D_{3000}^{kSZ} = 4.60 +/- 0.63 muK^2, consistent with earlier
measurements. We use the measured thermal SZ power and an analytic, thermal SZ
model calibrated with simulations to determine sigma8 = 0.807 +/- 0.016.
Modeling uncertainties involving the astrophysics of the intracluster medium
rather than the statistical uncertainty in the measured band powers are the
dominant source of uncertainty on sigma8 . We also place an upper limit on the
kinetic SZ power produced by patchy reionization; a companion paper uses these
limits to constrain the reionization history of the Universe.


  In this paper we prove that the $\zeta$-regularized product over all primes
is $\pi e^{\mu}$, where $\mu$ is closely related with the non-trivial zeros of
the $\zeta(s)$.


  Recent cosmological observations, such as the measurement of the primordial
4He abundance, CMB, and large scale structure, give preference to the existence
of extra radiation component, Delta N_nu > 0. The extra radiation may be
accounted for by particles which were in thermal equilibrium and decoupled
before the big bang nucleosynthesis. Broadly speaking, there are two
possibilities: 1) there are about 10 particles which have very weak couplings
to the standard model particles and decoupled much before the QCD phase
transition; 2) there is one or a few light particles with a reasonably strong
coupling to the plasma and it decouples after the QCD phase transition.
Focusing on the latter case, we find that a light chiral fermion is a suitable
candidate, which evades astrophysical constraints. Interestingly, such a
scenario may be confirmed at the LHC. As a concrete example, we show that such
a light fermion naturally appears in the E_6-inspired GUT.


  We study the geometric phase transitions that accompany the dynamic
rearrangement of vacuum under spontaneous violation of initial gauge symmetry.
The rearrangement may give rise to condensates of three types, namely the
scalar, axially symmetric, and entirely anisotropic condensates. The flat
space-time keeps being the Minkowski space in the only case of scalar
condensate. The anisotropic condensate having arisen, the respective anisotropy
occurs also in space-time. In this case the space-time filled with axially
symmetric condensate proves to be a flat relativistically invariant Finslerian
space with partially broken 3D isotropy, while the space-time filled with
entirely anisotropic condensate proves to be a flat relativistically invariant
Finslerian space with entirely broken 3D isotropy. The two Finslerian space
types are described briefly in the extended introduction to the work, while the
original part of the latter is devoted to determining observable 3-velocities
in the entirely anisotropic Finslerian event space. The main difficulties that
are overcome in solving that problem arose from the nonstandard form of the
light cone equation and from the necessity of correct introducing of a norm in
the linear vector space of rapidities.


  In task-oriented dialogue systems the dialogue state tracker (DST) component
is responsible for predicting the state of the dialogue based on the dialogue
history. Current DST approaches rely on a predefined domain ontology, a fact
that limits their effective usage for large scale conversational agents, where
the DST constantly needs to be interfaced with ever-increasing services and
APIs. Focused towards overcoming this drawback, we propose a domain-aware
dialogue state tracker, that is completely data-driven and it is modeled to
predict for dynamic service schemas. The proposed model utilizes domain and
slot information to extract both domain and slot specific representations for a
given dialogue, and then uses such representations to predict the values of the
corresponding slot. Integrating this mechanism with a pretrained language model
(i.e. BERT), our approach can effectively learn semantic relations.


  We discuss thw relations between the elastic and inelastic cross-sections
valid for the shadow and reflective modes of the elastic scattering.
Considerations are based on the unitarity arguments. It is shown that the
redistribution of the total interaction probability between the elastic and
inelastic interactions can lead to increasing ratio of
$\sigma_{el}(s)/\sigma_{tot}(s)$ at the LHC energies in presence of the
reflective scattering mode. The form of the inelastic overlap function becomes
peripheral due to the negative feedback. In the absorptive scattering mode, the
mechanism of this increase is a different one since the impact parameter
dependence of the inelastic interactions probability is central in this case. A
short notice is also given on the slope parameter and the leading contributions
to its energy dependence in the both modes.


  This article concerns with the existence of multiple positive solutions for
the following logarithmic Schr\"{o}dinger equation $$ \left\{ \begin{array}{lc}
-{\epsilon}^2\Delta u+ V(x)u=u \log u^2, & \mbox{in} \quad \mathbb{R}^{N}, \\
%u(x)>0, & \mbox{in} \quad \mathbb{R}^{N} \\ u \in H^1(\mathbb{R}^{N}), & \; \\
\end{array} \right. $$ where $\epsilon >0$, $N \geq 1$ and $V$ is a continuous
function with a global minimum. Using variational method, we prove that for
small enough $\epsilon>0$, the "shape" of the graph of the function $V$ affects
the number of nontrivial solutions.


  This work demonstrates an original and ultrasensitive approach for
surface-enhanced Raman spectroscopy (SERS) detection based on evaporation of
self-lubricating drops containing silver supraparticles. The developed method
detects an extremely low concentration of analyte that is enriched and
concentrated on sensitive SERS sites of the compact supraparticles formed from
drop evaporation. A low limit of detection of 10^-16 M is achieved for a model
hydrophobic compound rhodamine 6G (R6G). The quantitative analysis of R6G
concentration is obtained from 10^-5 to 10^-11 M. In addition, for a model
micro-pollutant in water triclosan, the detection limit of 10^-6 M is achieved
by using microliter sample solutions. The intensity of SERS detection in this
approach is robust to the dispersity of the nanoparticles in the drop but
became stronger after a longer drying time. The ultrasensitive detection
mechanism is the sequential process of concentration, extraction, and
absorption of the analyte during evaporation of self-lubrication drop and hot
spot generation for intensification of SERS signals. This novel approach for
sample preparation in ultrasensitive SERS detection can be applied to the
detection of chemical and biological signatures in areas such as environment
monitoring, food safety, and biomedical diagnostics.


  We theoretically analyze interference patterns of parametrically driven one
dimensional ultracold atomic gases. By modulating the interaction strength
periodically in time, we propose to excite collective modes in a pair of
independent one dimensional gases at energies corresponding to the drive
frequency. The excited collective modes lead to spatial oscillations in the
correlations of the interference pattern, which can be analyzed to obtain the
sound velocity of the collective modes. We discuss both bosonic and fermionic
systems, and how such experiments could be used to probe spin charge
separation.


  Click-through rate (CTR) prediction plays an important role in online
advertising and recommendation systems, which aims at estimating the
probability of a user clicking on a specific item. Feature interaction modeling
and user interest modeling methods are two popular domains in CTR prediction,
and they have been studied extensively in recent years. However, these methods
still suffer from two limitations. First, traditional methods regard item
attributes as ID features, while neglecting structure information and relation
dependencies among attributes. Second, when mining user interests from
user-item interactions, current models ignore user intents and item intents for
different attributes, which lacks interpretability. Based on this observation,
in this paper, we propose a novel approach Hierarchical Intention Embedding
Network (HIEN), which considers dependencies of attributes based on bottom-up
tree aggregation in the constructed attribute graph. HIEN also captures user
intents for different item attributes as well as item intents based on our
proposed hierarchical attention mechanism. Extensive experiments on both public
and production datasets show that the proposed model significantly outperforms
the state-of-the-art methods. In addition, HIEN can be applied as an input
module to state-of-the-art CTR prediction methods, bringing further performance
lift for these existing models that might already be intensively used in real
systems.


  This paper presents two novel approaches to increase performance bounds of
image steganography under the criteria of minimizing distortion. First, in
order to efficiently use the images' capacities, we propose using parallel
images in the embedding stage. The result is then used to prove sub-optimality
of the message distribution technique used by all cost based algorithms
including HUGO, S-UNIWARD, and HILL. Second, a new distribution approach is
presented to further improve the security of these algorithms. Experiments show
that this distribution method avoids embedding in smooth regions and thus
achieves a better performance, measured by state-of-the-art steganalysis, when
compared with the current used distribution.


  This Ph.D. thesis pursues two goals: The study of the geometrical structure
of two-dimensional quantum gravity and in particular its fractal nature. To
address these questions we review the continuum formalism of quantum gravity
with special focus on the scaling properties of the theory. We discuss several
concepts of fractal dimensions which characterize the extrinsic and intrinsic
geometry of quantum gravity. This work is partly based on work done in
collaboration with Jan Ambj{\o}rn, Dimitrij Boulatov, Jakob L. Nielsen and
Yoshiyuki Watabiki (1997).
  The other goal is the discussion of the discretization of quantum gravity and
to address the so called quantum failure of Regge calculus. We review dynamical
triangulations and show that it agrees with the continuum theory in two
dimensions. Then we discuss Regge calculus and prove that a continuum limit
cannot be taken in a sensible way and that it does not reproduce continuum
results. This work is partly based on work done in collaboration with Jan
Ambj{\o}rn, Jakob L. Nielsen and George Savvidy (1997).


  A rapidly deployable and cost-effective railroad crossing early warning
system integrated with the railway system is attractive due to its protection
of the unmanned grade crossings, which requires a warning system with
long-distance communication link. In this paper, we investigate the problem of
suitable antenna selection for such a railway warning system First, the antenna
criteria for railroad crossing safety applications are described based on
practical system considerations, the safe distances on the road and on the
railway. Then, the optimal antenna pattern is derived theoretically to get the
smallest size which fits for the practical installation. We also conducted a
feasibility study of an array antenna through measurements on a near field
scanner.


  We perform a comprehensive cosmological study of the $H_0$ tension between
the direct local measurement and the model-dependent value inferred from the
Cosmic Microwave Background. With the recent measurement of $H_0$ this tension
has raised to more than $3\sigma$. We consider changes in the early time
physics without modifying the late time cosmology. We also reconstruct the late
time expansion history in a model independent way with minimal assumptions
using distances measures from Baryon Acoustic Oscillations and Type Ia
Supernovae, finding that at $z<0.6$ the recovered shape of the expansion
history is less than 5 % different than that of a standard LCDM model. These
probes also provide a model insensitive constraint on the low-redshift standard
ruler, measuring directly the combination $r_s h$ where $H_0=h \times 100$
km/s/Mpc and $r_s$ is the sound horizon at radiation drag (the standard ruler),
traditionally constrained by CMB observations. Thus $r_s$ and $H_0$ provide
absolute scales for distance measurements (anchors) at opposite ends of the
observable Universe. We calibrate the cosmic distance ladder and obtain a
model-independent determination of the standard ruler for acoustic scale,
$r_s$. The tension in $H_0$ reflects a mismatch between our determination of
$r_s$ and its standard, CMB-inferred value. Without including high-l Planck CMB
polarization data (i.e., only considering the "recommended baseline" low-l
polarisation and temperature and the high l temperature data), a modification
of the early-time physics to include a component of dark radiation with an
effective number of species around 0.4 would reconcile the CMB-inferred
constraints, and the local $H_0$ and standard ruler determinations. The
inclusion of the "preliminary" high-l Planck CMB polarisation data disfavours
this solution.


  We analyze a sample of 139 near-Earth asteroids (NEAs), defined as those that
reach perihelion distances $q < 1.3$ au, and that also fulfill the conditions
of approaching or crossing Jupiter's orbit (aphelion distances $Q > 4.8$ au),
having Tisserand parameters $2 < T < 3$ and orbital periods $P < 20$ yr. In
order to compare the dynamics, we also analyze a sample of 42 Jupiter family
comets (JFCs) in near-Earth orbits, i.e. with $q < 1.3$ au. We integrated the
orbits of these two samples for $10^4$ yr in the past and in the future. We
find that the great majority of the NEAs move on stable orbits during the
considered period, and that a large proportion of them are in one of the main
mean motion resonances with Jupiter, in particular the 2:1. We find a strong
coupling between the perihelion distance and the inclination in the motion of
most NEAs, due to Kozai mechanism, that generates many sungrazers. On the other
hand, most JFCs are found to move on very unstable orbits, showing large
variations in their perihelion distances in the last few $10^2 - 10^3$ yr,
which suggests a rather recent capture in their current near-Earth orbits. Even
though most NEAs of our sample move in typical 'asteroidal' orbits, we detect a
small group of NEAs whose orbits are highly unstable, resembling those of the
JFCs. These are: 1997 SE5, 2000 DN1, 2001 XQ, 2002 GJ8, 2002 RN38, 2003 CC11,
2003 WY25, 2009 CR2, and 2011 OL51. These objects might be inactive comets, and
indeed 2003 WY25 has been associated with comet Blanpain, and it is now
designed as comet 289P/Blanpain. Under the assumption that these objects are
inactive comets, we can set an upper limit of $\sim 0.17$ to the fraction of
NEAs with $Q > 4.8$ au of cometary origin, but it could be even lower if the
NEAs in unstable orbits listed before turn out to be {\it bona fide} asteroids
from the main belt.


  We present a complete survey of current star formation in the Perseus
molecular cloud, made at 850 and 450 micron with SCUBA at the JCMT. Covering 3
deg^2, this submillimetre continuum survey for protostellar activity is second
in size only to that of rho Ophiuchus (Johnstone et al. 2004). Complete above
0.4 msun (5 sigma detection in a 14'' beam), we detect a total of 91 protostars
and prestellar cores. Of these, 80% lie in clusters, representative of star
formation across the Galaxy. Two of the groups of cores are associated with the
young stellar clusters IC348 and NGC1333, and are consistent with a steady or
reduced star formation rate in the last 0.5 Myr, but not an increasing one. In
Perseus, 40--60% of cores are in small clusters (< 50 msun) and isolated
objects, much more than the 10% suggested from infrared studies. Complementing
the dust continuum, we present a C^18O map of the whole cloud at 1' resolution.
The gas and dust show filamentary structure of the dense gas on large and small
scales, with the high column density filaments breaking up into clusters of
cores. The filament mass per unit length is 5--11 msun per 0.1 pc. Given these
filament masses, there is no requirement for substantial large scale flows
along or onto the filaments in order to gather sufficient material for star
formation. We find that the probability of finding a submillimetre core is a
strongly increasing function of column density, as measured by C^18O integrated
intensity, prob(core) proportional to I^3.0. This power law relation holds down
to low column density, suggesting that there is no A_v threshold for star
formation in Perseus, unless all the low-A_v submm cores can be demonstrated to
be older protostars which have begun to lose their natal molecular cloud.


  For large classes of even-dimensional Riemannian manifolds $(M,g)$, we
construct and analyze conformally invariant random fields. These centered
Gaussian fields $h=h_g$, called co-polyharmonic Gaussian fields, are
characterized by their covariance kernels $k$ which exhibit a precise
logarithmic divergence: $|k(x,y)-\log\frac1{d(x,y)}|\le C$. They share a
fundamental quasi-invariance property under conformal transformations.
  In terms of the co-polyharmonic Gaussian field $h$, we define the quantum
Liouville measure, a random measure on $M$, heuristically given as $$
d\mu_g^{h}(x):= e^{\gamma h(x)-\frac{\gamma^2}2k(x,x)}\,d \text{vol}_g(x)$$ and
rigorously obtained as almost sure weak limit of the right-hand side with $h$
replaced by suitable regular approximations $h_\ell, \ell\in{\mathbb N}$. In
terms on the quantum Liouville measure, we define the Liouville Brownian motion
on $M$ and the random GJMS operators.
  Finally, we present an approach to a conformal field theory in arbitrary even
dimensions with an ansatz based on Branson's $Q$-curvature: we give a rigorous
meaning to the Polyakov-Liouville measure $$ d\boldsymbol{\nu}^*_g(h)
=\frac1{Z^*_g} \exp\Big(- \int \Theta\,Q_g h + m e^{\gamma h} d
\text{vol}_g\Big) \exp\Big(-\frac{a_n}{2} {\mathfrak p}_g(h,h)\Big) dh, $$ and
we derive the corresponding conformal anomaly.
  The set of admissible manifolds is conformally invariant. It includes all
compact 2-dimensional Riemannian manifolds, all compact non-negatively curved
Einstein manifolds of even dimension, and large classes of compact hyperbolic
manifolds of even dimension. However, not every compact even-dimensional
Riemannian manifold is admissible.
  Our results rely on new sharp estimates for heat kernels and higher order
Green kernels on arbitrary compact manifolds.


  This paper is an empirical study of the distributed deep learning for
question answering subtasks: answer selection and question classification.
Comparison studies of SGD, MSGD, ADADELTA, ADAGRAD, ADAM/ADAMAX, RMSPROP,
DOWNPOUR and EASGD/EAMSGD algorithms have been presented. Experimental results
show that the distributed framework based on the message passing interface can
accelerate the convergence speed at a sublinear scale. This paper demonstrates
the importance of distributed training. For example, with 48 workers, a 24x
speedup is achievable for the answer selection task and running time is
decreased from 138.2 hours to 5.81 hours, which will increase the productivity
significantly.


  User behaviour analysis based on traffic log in wireless networks can be
beneficial to many fields in real life: not only for commercial purposes, but
also for improving network service quality and social management. We cluster
users into groups marked by the most frequently visited websites to find their
preferences. In this paper, we propose a user behaviour model based on Topic
Model from document classification problems. We use the logarithmic TF-IDF
(term frequency - inverse document frequency) weighing to form a
high-dimensional sparse feature matrix. Then we apply LSA (Latent semantic
analysis) to deduce the latent topic distribution and generate a
low-dimensional dense feature matrix. K-means++, which is a classic clustering
algorithm, is then applied to the dense feature matrix and several
interpretable user clusters are found. Moreover, by combining the clustering
results with additional demographical information, including age, gender, and
financial information, we are able to uncover more realistic implications from
the clustering results.


Retraction due to significant oversight


  Motivated by the current Coronavirus Disease (COVID-19) pandemic, which is
due to the SARS-CoV-2 virus, and the important problem of forecasting daily
deaths and cumulative deaths, this paper examines the construction of
prediction regions or intervals under the Poisson regression model and for an
over-dispersed Poisson regression model. For the Poisson regression model,
several prediction regions are developed and their performance are compared
through simulation studies. The methods are applied to the problem of
forecasting daily and cumulative deaths in the United States (US) due to
COVID-19. To examine their performance relative to what actually happened,
daily deaths data until May 15th were used to forecast cumulative deaths by
June 1st. It was observed that there is over-dispersion in the observed data
relative to the Poisson regression model. An over-dispersed Poisson regression
model is therefore proposed. This new model builds on frailty ideas in Survival
Analysis and over-dispersion is quantified through an additional parameter. The
Poisson regression model is a hidden model in this over-dispersed Poisson
regression model and obtains as a limiting case when the over-dispersion
parameter increases to infinity. A prediction region for the cumulative number
of US deaths due to COVID-19 by July 16th, given the data until July 2nd, is
presented. Finally, the paper discusses limitations of proposed procedures and
mentions open research problems, as well as the dangers and pitfalls when
forecasting on a long horizon, with focus on this pandemic where events, both
foreseen and unforeseen, could have huge impacts on point predictions and
prediction regions.


  The $2$kth pseudomoments of the Riemann zeta function $\zeta(s)$ are,
following Conrey and Gamburd, the $2k$th integral moments of the partial sums
of $\zeta(s)$ on the critical line. For fixed $k>1/2$, these moments are known
to grow like $(\log N)^{k^2}$, where $N$ is the length of the partial sum, but
the true order of magnitude remains unknown when $k\le 1/2$. We deduce new
Hardy--Littlewood inequalities and apply one of them to improve on an earlier
asymptotic estimate when $k\to\infty$. In the case $k<1/2$, we consider
pseudomoments of $\zeta^{\alpha}(s)$ for $\alpha>1$ and the question of whether
the lower bound $(\log N)^{k^2\alpha^2}$ known from earlier work yields the
true growth rate. Using ideas from recent work of Harper, Nikeghbali, and
Radziwi{\l\l} and some probabilistic estimates of Harper, we obtain the
somewhat unexpected result that these pseudomements are bounded below by $\log
N$ to a power larger than $k^2\alpha^2$ when $k<1/e$ and $N$ is sufficiently
large.


  In this Letter we make progress on a longstanding open problem of Aaronson
and Ambainis [Theory of Computing 1, 47 (2005)]: we show that if A is the
adjacency matrix of a sufficiently sparse low-dimensional graph then the
unitary operator e^{itA} can be approximated by a unitary operator U(t) whose
sparsity pattern is exactly that of a low-dimensional graph which gets more
dense as |t| increases. Secondly, we show that if U is a sparse unitary
operator with a gap \Delta in its spectrum, then there exists an approximate
logarithm H of U which is also sparse. The sparsity pattern of H gets more
dense as 1/\Delta increases. These two results can be interpreted as a way to
convert between local continuous-time and local discrete-time processes. As an
example we show that the discrete-time coined quantum walk can be realised as
an approximately local continuous-time quantum walk. Finally, we use our
construction to provide a definition for a fractional quantum fourier
transform.


  The reverse split rank of an integral polyhedron P is defined as the supremum
of the split ranks of all rational polyhedra whose integer hull is P. Already
in R^3 there exist polyhedra with infinite reverse split rank. We give a
geometric characterization of the integral polyhedra in R^n with infinite
reverse split rank.


  The superfluidity of neutron matter in the channel $^1 S_0$ is studied by
taking into account the effect of the ground-state correlations in the
self-energy. To this purpose the gap equation has been solved within the
generalized Gorkov approach. A sizeable suppression of the energy gap is driven
by the quasi-particle strength around the Fermi surface.


  This paper seeks to combine differential game theory with the
actor-critic-identifier architecture to determine forward-in-time, approximate
optimal controllers for formation tracking in multi-agent systems, where the
agents have uncertain heterogeneous nonlinear dynamics. A continuous control
strategy is proposed, using communication feedback from extended neighbors on a
communication topology that has a spanning tree. A model-based reinforcement
learning technique is developed to cooperatively control a group of agents to
track a trajectory in a desired formation. Simulation results are presented to
demonstrate the performance of the developed technique.


  The recent breakthroughs of deep reinforcement learning (DRL) technique in
Alpha Go and playing Atari have set a good example in handling large state and
actions spaces of complicated control problems. The DRL technique is comprised
of (i) an offline deep neural network (DNN) construction phase, which derives
the correlation between each state-action pair of the system and its value
function, and (ii) an online deep Q-learning phase, which adaptively derives
the optimal action and updates value estimates. In this paper, we first present
the general DRL framework, which can be widely utilized in many applications
with different optimization objectives. This is followed by the introduction of
three specific applications: the cloud computing resource allocation problem,
the residential smart grid task scheduling problem, and building HVAC system
optimal control problem. The effectiveness of the DRL technique in these three
cyber-physical applications have been validated. Finally, this paper
investigates the stochastic computing-based hardware implementations of the DRL
framework, which consumes a significant improvement in area efficiency and
power consumption compared with binary-based implementation counterparts.


  We investigate the concept of dominion (in the sense of Isbell) in several
varieties of nilpotent groups. We obtain a full description of dominions in the
variety of nilpotent groups of class at most two. Then we look at the behavior
of dominions of subgroups of groups in ${\cal N}_2$ when taken in the context
of ${\cal N}_c$ with $c>2$. Finally we establish the existence of nontrivial
dominions in the category of all nilpotent groups.


  We present an axiomatization of non-relativistic Quantum Mechanics for a
system with an arbitrary number of components. The interpretation of our system
of axioms is realistic and objective. The EPR paradox and its relation with
realism is discussed in this framework. It is shown that there is no
contradiction between realism and recent experimental results.


  Using sensors as a means to achieve self-awareness and artificial
intelligence for decision-making, may be a way to make complex systems
self-adaptive, autonomous and resilient. Investigating the combination of
distributed artificial intelligence methods and bio-inspired robotics can
provide results that will be helpful for implementing autonomy of such robots
and other complex systems. In this paper, we describe Distributed Artificial
Intelligence application area, the most common examples of continuum robots and
provide a description of our first steps towards implementing distributed
control.


  We revise the procedure proposed by Balassa to infer comparative advantage,
which is a standard tool, in Economics, to analyze specialization (of
countries, regions, etc.). Balassa's approach compares the export of a product
for each country with what would be expected from a benchmark based on the
total volumes of countries and products flows. Based on results in the
literature, we show that the implementation of Balassa's idea generates a bias:
the prescription of the maximum likelihood used to calculate the parameters of
the benchmark model conflicts with the model's definition. Moreover, Balassa's
approach does not implement any statistical validation. Hence, we propose an
alternative procedure to overcome such a limitation, based upon the framework
of entropy maximisation and implementing a proper test of hypothesis: the `key
products' of a country are, now, the ones whose production is significantly
larger than expected, under a null-model constraining the same amount of
information employed by Balassa's approach. What we found is that countries
diversification is always observed, regardless of the strictness of the
validation procedure. Besides, the ranking of countries' fitness is only
partially affected by the details of the validation scheme employed for the
analysis while large differences are found to affect the rankings of products
Complexities. The routine for implementing the entropy-based filtering
procedures employed here is freely available through the official Python
Package Index PyPI.


  The quantum superposition principle has been extensively utilized in the
quantum mechanical description of the bonding phenomenon. It explains the
emergence of delocalized molecular orbitals and provides a recipe for the
construction of near-exact electronic wavefunctions. On the other hand, its
existence in composite systems may give rise to nonclassical correlations that
are regarded now as a resource in quantum technologies. Here, we approach the
electronic ground states of three prototypical molecules from the point of view
of fermionic information theory. For the first time in the literature, we
properly decompose the pairwise orbital correlations into their classical and
quantum parts in the presence of superselection rules. We observe that quantum
orbital correlations can be stronger than classical orbital correlations though
not often. Also, quantum orbital correlations can survive even in the absence
of orbital entanglement depending on the symmetries of the constituent
orbitals. Finally, we demonstrate that orbital entanglement would be
underestimated if the orbital density matrices were treated as qubit states.


  This paper is concerned with a detailed comparison of two different
abstraction techniques for the construction of finite state symbolic models for
controller synthesis of hybrid systems. Namely, we compare quotient based
abstractions (QBA), with different realizations of strongest (asynchronous)
$l$-complete approximations (SAlCA) Even though the idea behind their
construction is very similar, we show that they are generally incomparable both
in terms of behavioral inclusion and similarity relations. We therefore derive
necessary and sufficient conditions for QBA to coincide with particular
realizations of SAlCA. Depending on the original system, either QBA or SAlCA
can be a tighter abstraction.


  In many statistical problems, a more coarse-grained model may be suitable for
population-level behaviour, whereas a more detailed model is appropriate for
accurate modelling of individual behaviour. This raises the question of how to
integrate both types of models. Methods such as posterior regularization follow
the idea of generalized moment matching, in that they allow matching
expectations between two models, but sometimes both models are most
conveniently expressed as latent variable models. We propose latent Bayesian
melding, which is motivated by averaging the distributions over populations
statistics of both the individual-level and the population-level models under a
logarithmic opinion pool framework. In a case study on electricity
disaggregation, which is a type of single-channel blind source separation
problem, we show that latent Bayesian melding leads to significantly more
accurate predictions than an approach based solely on generalized moment
matching.


  This paper concentrates on building a multi-antenna FPGA based Channel
Sounder with single transmitter and multiple receivers to realize wireless
propagation characteristics of an indoor environment. A DSSS signal (spread
with a real maximum length PN sequence) is transmitted, which is correlated
with the same PN sequence at each receiver to obtain the power delay profile .
Multiple power delay profiles are averaged and the result is then sent to host.
To utilize high bandwidth, the computationally expensive tasks related to
generation and parallel correlation of PN sequences are moved to the FPGA
present in each USRP (Universal Software Radio Peripheral). Channel sounder
blocks were built using Vivado HLS and integrated with RFNoC (RF Network on
Chip) framework, which were then used on USRP X310 devices.


  We study masses and decay widths of positive and negative parity nucleons
using a three-flavor parity doublet model, in which we introduce three
representations, $\left[({\bf 3} , \bar{{\bf 3}})\oplus (\bar{{\bf 3}} , {\bf
3})\right]$, $\left[({\bf 3} , {\bf 6}) \oplus ({\bf 6}, {\bf 3})\right]$, and
$\left[({\bf 8} , {\bf 1}) \oplus ({\bf 1} , {\bf 8})\right]$ of the chiral
U$(3)_{\rm L}\times$U$(3)_{\rm R}$ symmetry. We find an extended version of the
Goldberger-Treiman relation among the mass differences and the coupling
constants for pionic transitions. This relation leads to an upper bound for the
decay width of $N(1440) \rightarrow N(939) + \pi$ independently of the model
parameters. We perform the numerical fitting of the model parameters and derive
several predictions, which can be tested in future experiments or lattice QCD
analysis. Furthermore, when we use the axial coupling of the excited nucleons
obtained from lattice QCD analyses as inputs, we find that the ground state
nucleon $N(939)$ consists of about 80% of $\left[({\bf 3} , {\bf 6}) \oplus
({\bf 6}, {\bf 3})\right]$ component, and that the chiral invariant mass of
$N(939)$ is roughly $500$ -- $800$MeV.