  Frame theory is a powerful tool in the domain of signal processing and
communication. Among its numerous configurations, the ones which have drawn
much attention recently are Equiangular Tight Frame (ETF) and Grassmannian
Frame. These frames both have some kind of optimality in coherence, thus bring
robustness or optimal performance in applications such as digital fingerprint,
erasure channels, and Compressive Sensing. However, too strict constraint on
existence and construction of ETF and Grassmannian Frame became the main
obstacle for widespread use. In this paper, we propose a new configuration of
frame: Quasi-Equiangular Frame, as a compromise but more convenient and
flexible approximation of ETF and Grassmannian Frame. We will give formal
definition of Quasi-Equiangular Frame and analyze its relationship with ETF and
Grassmannian frame. Furthermore, for popularity of ETF and Grassmannian frame
in Compressive Sensing, we utilize the technique of random matrices to obtain
asymptotical concentration estimation of the Restricted Isometry Constant (RIC)
of Quasi-Equiangular Frame with respect to its key parameter.


  Supporting e-Science in the EGI e-Infrastructure requires extensive and
reliable software, for advanced computing use, deployed across over
approximately 300 European and worldwide data centers. The Unified Middleware
Distribution (UMD) and Cloud Middleware Distribution (CMD) are the channels to
deliver the software for the EGI e-Infrastructure consumption. The software is
compiled, validated and distributed following the Software Provisioning Process
(SWPP), where the Quality Criteria (QC) definition sets the minimum quality
requirements for EGI acceptance. The growing number of software components
currently existing within UMD and CMD distributions hinders the application of
the traditional, manual-based validation mechanisms, thus driving the adoption
of automated solutions. This paper presents umd-verification, an open-source
tool that enforces the fulfillment of the QC requirements in an automated way
for the continuous validation of the software products for scientific disposal.
The umd-verification tool has been successfully integrated within the SWPP
pipeline and is progressively supporting the full validation of the products in
the UMD and CMD repositories. While the cost of supporting new products is
dependant on the availability of Infrastructure as Code solutions to take over
the deployment and high test coverage, the results obtained for the already
integrated products are promising, as the time invested in the validation of
products has been drastically reduced. Furthermore, automation adoption has
brought along benefits for the reliability of the process, such as the removal
of human-associated errors or the risk of regression of previously tested
functionalities.


  Graph pooling methods have been widely used on downsampling graphs, achieving
impressive results on multiple graph-level tasks like graph classification and
graph generation. An important line called node dropping pooling aims at
exploiting learnable scoring functions to drop nodes with comparatively lower
significance scores. However, existing node dropping methods suffer from two
limitations: (1) for each pooled node, these models struggle to capture
long-range dependencies since they mainly take GNNs as the backbones; (2)
pooling only the highest-scoring nodes tends to preserve similar nodes, thus
discarding the affluent information of low-scoring nodes. To address these
issues, we propose a Graph Transformer Pooling method termed GTPool, which
introduces Transformer to node dropping pooling to efficiently capture
long-range pairwise interactions and meanwhile sample nodes diversely.
Specifically, we design a scoring module based on the self-attention mechanism
that takes both global context and local context into consideration, measuring
the importance of nodes more comprehensively. GTPool further utilizes a
diversified sampling method named Roulette Wheel Sampling (RWS) that is able to
flexibly preserve nodes across different scoring intervals instead of only
higher scoring nodes. In this way, GTPool could effectively obtain long-range
information and select more representative nodes. Extensive experiments on 11
benchmark datasets demonstrate the superiority of GTPool over existing popular
graph pooling methods.


  We study problems relating to the D(2)-Problem for metacyclic groups of type
$G(p,p-1)$ where $p$ is an odd prime. Specifically we build on Nadim's thesis
\cite{Jamil}, which showed that the $\mathbb{Z}[G(5,4)]$-module $\mathbb{Z}$
admits a diagonal resolution and a minimal representative for the third syzygy
$\Omega_3(\mathbb{Z})$ is $R(2)\oplus[y-1)$. Motivated by this result, we show
that the $\mathbb{Z}[G(p,p-1)]$-module $R(2)\oplus[y-1)$ is both full and
straight for any odd prime $p$. Given Johnson's work on the D(2)-Problem
\cite{D2}, this leads to the conclusion that $G(5,4)$ satisfies the
D(2)-property, as well as providing a sufficient condition for the
D(2)-property to hold for $G(p,p-1)$, namely the condition that
$R(2)\oplus[y-1)$ is a minimal representative for $\Omega_3(\mathbb{Z})$ over
$\mathbb{Z}[G(p,p-1)]$, which we refer to as the condition M(p). Following this
result, we prove a theorem which simplifies the calculations required to show
that the condition M(p) holds. Finally, we carry out these calculations in the
case where $p=7$ and prove that the condition M(7) holds, which is sufficient
to show that $G(7,6)$ satisfies the D(2)-property.


  We calculate the induced elastic-interaction between pointwise membrane
inclusions that locally interact up to quadratic order with the membrane
curvature tensor. For isotropic inclusions, we recover the usual interaction
proportional to the inverse fourth power of the separation, however with a
prefactor showing a non-trivial dependence on the rigidity $\Gamma$ of the
quadratic potential. In the large $\Gamma$ limit, corresponding to ``hard''
inclusions, we recover the standard prefactor first obtained by Goulian et al.
[Europhys. Lett. \textbf{22}, 145 (1993)]. In the small $\Gamma$ limit,
corresponding to "soft" inclusions, we recover the recent result of Marchenko
and Misbah [Eur. Phys. J. E \textbf{8}, 477 (2002)]. This shows that the latter
result bears no fundamental discrepancy with previous works, but simply
corresponds to the limit of soft inclusions. We discuss how the same inclusion
can be depicted as hard or soft according to the degree of coarse-graining of
the pointwise description. Finally, we argue that conical transmembrane
proteins should be fundamentally considered as hard inclusions.


  We develop a technique for generating a set of optimized local basis
functions to solve models in the Kohn-Sham density functional theory for both
insulating and metallic systems. The optimized local basis functions are
obtained by solving a minimization problem in an admissible set determined by a
large number of primitive basis functions. Using the optimized local basis set,
the electron energy and the atomic force can be calculated accurately with a
small number of basis functions. The Pulay force is systematically controlled
and is not required to be calculated, which makes the optimized local basis set
an ideal tool for ab initio molecular dynamics and structure optimization. We
also propose a preconditioned Newton-GMRES method to obtain the optimized local
basis functions in practice. The optimized local basis set is able to achieve
high accuracy with a small number of basis functions per atom when applied to a
one dimensional model problem.


  We show by explicit construction the existence of various four dimensional
models of type II superstrings with N=2 supersymmetry, purely vector multiplet
spectrum and no hypermultiplets. Among these, two are of special interest, at
the field theory level they correspond to the two exceptional N=2
supergravities of the magic square that have the same massless scalar field
content as pure N=6 supergravity and N=3 supergravity coupled to three extra
vector multiplets. The N=2 model of the magic square that is associated to N=6
supergravity is very peculiar since not only the scalar degrees of freedom but
all the bosonic massless degrees of freedom are the same in both theories.
  All presented hyper-free N=2 models are based on asymmetric orbifold
constructions with N=(4,1) world-sheet superconformal symmetry and utilize the
2d fermionic construction techniques. The two exceptional N=2 models of the
magic square are constructed via a "twisting mechanism" that eliminates the
extra gravitini of the N=6 and N=3 extended supergravities and creates at the
same time the extra spin-1/2 fermions and spin-1 gauge bosons which are
necessary to balance the numbers of bosons and fermions. Theories of the magic
square with the same amount of supersymmetry in three and five space-time
dimensions are constructed as well, via stringy reduction and oxidation from
the corresponding four-dimensional models.


  A theorem of the first author states that the cotangent bundle of the type
$A$ Grassmannian variety can be embedded as an open subset of a smooth Schubert
variety in a two-step affine partial flag variety. We extend this result to
cotangent bundles of cominuscule generalized Grassmannians of arbitrary Lie
type.


  The behavior of dense mixtures of two topologically different
diblock-copolymer (CP) chains, viz., linear(L)-CP and ring(R)-CP of same
molecular weight which forms lamellae is studied under confinement by two
non-selective substrates. The effect of varying interaction strength between
L-CP and R-CP, from purely repulsive ({\it demixed state}) to weakly attractive
({\it mixed state}), on the morphology, domain size, chain conformations and
distribution of chains in the film are investigated. In the demixed state,
collective structure factor $S(q)$ shows a split of the predominant peak
indicating the presence of two dominant length scales. While there is only one
predominant peak in the mixed state, and hence a lamellar structure with single
domain size. We show that the peak position $q*$ of $S(q)$ can be varied with
the L/R interaction strength and thus allow one to control domain size by
tuning L/R interaction strength without altering the chain size. We further
characterize the chain size and illustrate that this domain size variation is a
consequence of the variation in the size of L-CPs. Furthermore, results on the
average instantaneous shape of R/L-CP reveal that their shapes are very
different both in bulk and near the substrate, and R-CP assumes an oblate shape
near the substrate. This shape/size difference leads to the segregation of
R-CPs near the polymer-substrate interface and hence a relatively higher
density of R-CPs at the interface.


  Scenario bouncing can give the cosmology singularity problem a possible way
out. Finding a solution for the universe's bouncing model requires proper
estimation of the state equation. We present two such state equations that give
us the solution for a bounce. One such case is the exotic radiation, where we
assumed that exotic radiation dominated the universe during the bounce
occurrence. We also considered another case where quintom matter scenario
existed previously, and the newly proposed exotic radiation scenario coexisted.
In these two cases, we have shown that all the necessary conditions for the
bounce are fulfilled. Such new ways certainly increase support and flexibility
for the bouncing universe model.


  The low-temperature (T = 17.5 K) structure of titanium(III)-oxybromide,
TiOBr, is reported as a two-fold superstructure of the crystal structure at
room temperature. Weak superlattice reflections could be measured with
synchrotron radiation x-rays, and they were analysed by structure refinements
employing superspace techniques. Both the low temperature and room temperature
tructures of TiOBr are isostructural to the corresponding structures of TiOCl.
The results indicate that at low temperatures TiOBr is in a spin-Peierls state
similar to TiOCl, but with the modulations and relevant interactions smaller
than in the latter compound.


  At temperatures below the magnetic anisotropy energy, monodomain magnetic
systems (small particles, nanomagnetic devices, etc.) must relax quantum
mechanically. This quantum relaxation must be mediated by the coupling to both
nuclear spins and phonons (and electrons if either particle or substrate is
conducting. We analyze the effect of each of these couplings, and then combine
them. Conducting systems can be modelled by a "giant Kondo" Hamiltonian, with
nuclear spins added in as well. At low temperatures, even microscopic particles
on a conducting substrate (containing only $10-50$ spins) will have their
magnetisation frozen over millenia by a combination of electronic dissipation
and the "degeneracy blocking" caused by nuclear spins. Raising the temperature
leads to a sudden unblocking of the spin dynamics at a well defined
temperature. Insulating systems are quite different. The relaxation is strongly
enhanced by the coupling to nuclear spins. At short times the magnetisation of
an ensemble of particles relaxes logarithmically in time, after an initial very
fast decay; this relaxation proceeds entirely via the nuclear spins. At longer
times phonons take over, but the decay rate is still governed by the
temperature-dependent nuclear bias field acting on the particles - decay may be
exponential or power-law depending on the temperature. The most surprising
feature of the results is the pivotal role played by the nuclear spins. The
results are relevant to any experiments on magnetic particles in which
interparticle dipolar interactions are unimportant. They are also relevant to
future magnetic device technology.


  We investigate the geometry of closed, orientable, hyperbolic $3$-manifolds
whose fundamental groups are $k$-free for a given integer $k\ge 3$. We show
that any such manifold $M$ contains a point $P$ of $M$ with the following
property: If $S$ is the set of elements of $\pi_1(M,P)$ represented by loops of
length $<\log(2k-1)$, then for every subset $T \subset S$, we have ${\rm rank}\
T \le k-3$. This generalizes to all $k\ge3$ results proved in [6] and [10],
which have been used to relate the volume of a hyperbolic manifold to its
topological properties, and it strictly improves on the result obtained in [11]
for $k=5$. The proof avoids the use of results about ranks of joins and
intersections in free groups that were used in [10] and [11].


  Implicit generative models, which do not return likelihood values, such as
generative adversarial networks and diffusion models, have become prevalent in
recent years. While it is true that these models have shown remarkable results,
evaluating their performance is challenging. This issue is of vital importance
to push research forward and identify meaningful gains from random noise.
Currently, heuristic metrics such as the Inception score (IS) and Frechet
Inception Distance (FID) are the most common evaluation metrics, but what they
measure is not entirely clear. Additionally, there are questions regarding how
meaningful their score actually is. In this work, we study the evaluation
metrics of generative models by generating a high-quality synthetic dataset on
which we can estimate classical metrics for comparison. Our study shows that
while FID and IS do correlate to several f-divergences, their ranking of close
models can vary considerably making them problematic when used for fain-grained
comparison. We further used this experimental setting to study which evaluation
metric best correlates with our probabilistic metrics. Lastly, we look into the
base features used for metrics such as FID.


  We present a phenomenological and numerical study of strong Alfv\'enic
turbulence in a magnetically dominated collisionless relativistic plasma with a
strong background magnetic field. In contrast with the non-relativistic case,
the energy in such turbulence is contained in magnetic and electric
fluctuations. We argue that such turbulence is analogous to turbulence in a
strongly magnetized non-relativistic plasma in the regime of broken
quasi-neutrality. Our 2D particle-in-cell numerical simulations of turbulence
in a relativistic pair plasma find that the spectrum of the total energy has
the scaling $k^{-3/2}$, while the difference between the magnetic and electric
energies, the so-called residual energy, has the scaling $k^{-2.4}$. The
electric and magnetic fluctuations at scale $\ell$ exhibit dynamic alignment
with the alignment-angle scaling close to $\cos\phi_\ell\propto \ell^{1/4}$. At
scales smaller than the (relativistic) plasma inertial scale, the energy
spectrum of relativistic inertial Alfv\'en turbulence steepens to $k^{-3.5}$.


  Motivated by a recent finding of a spin-flop phenomenon in a system without
anisotropy in spin space reported in the S=1/2 Heisenberg antiferromagnet on
the square-kagome lattice, we study the S=1/2 Heisenberg antiferromagnets on
two other lattices composed of vertex-sharing triangles by the numerical
diagonalization method. One is a novel lattice including a shuriken shape with
four teeth; the other is the kagome lattice with
$\sqrt{3}\times\sqrt{3}$-structure distortion, which includes a shuriken shape
with six teeth. We find in the magnetization processes of these systems that a
magnetization jump accompanied by a spin-flop phenomenon occurs at the
higher-field-side edge of the magnetization plateau at one-third the height of
saturation. This finding indicates that the spin-flop phenomenon found in the
isotropic system on the square-kagome lattice is not an exceptional case.


  We investigate a class of models of topological inflation in which a
super-Hubble-sized global monopole seeds inflation. These models are attractive
since inflation starts from rather generic initial conditions, but their not so
attractive feature is that, unless symmetry is again restored, inflation never
ends. In this work we show that, in presence of another nonminimally coupled
scalar field, that is both quadratically and quartically coupled to the Ricci
scalar, inflation naturally ends, representing an elegant solution to the
graceful exit problem of topological inflation. While the monopole core grows
during inflation, the growth stops after inflation, such that the monopole
eventually enters the Hubble radius, and shrinks to its Minkowski space size,
rendering it immaterial for the subsequent Universe's dynamics. Furthermore, we
find that our model can produce cosmological perturbations that source CMB
temperature fluctuations and seed large scale structure statistically
consistent (within one standard deviation) with all available data. In
particular, for small and (in our convention) negative nonminimal couplings,
the scalar spectral index can be as large as $n_s\simeq 0.955$, which is about
one standard deviation lower than the central value quoted by the most recent
Planck Collaboration.


  We observe an experimental signature of the role of the phonons in spin
relaxation between triplet and singlet states in a two-electron quantum dot.
Using both the external magnetic field and the electrostatic confinement
potential, we change the singlet-triplet energy splitting from 1.3 meV to zero
and observe that the spin relaxation time depends non-monotonously on the
energy splitting. A simple theoretical model is derived to capture the
underlying physical mechanism. The present experiment confirms that spin-flip
energy is dissipated in the phonon bath.


  We consider, in the electroweak standard model context, several left-right
asymmetries in $\mu e$ elastic scattering at fixed target and collider
experiments. For the former case, we show that the muon mass effects are
important in a wide energy range. We also show that these asymmetries are
sensitive to the electroweak mixing angle $\theta_W$. The effect of an extra
$Z'$ neutral vector boson appearing in a 331 model is also considered. The
capabilities of these asymmetries in the search of this extra $Z'$ are
addressed.


  We construct some new brane solutions in M-theory, based on the minimal
surfaces. In particular, we consider the anti-self-dual Nutku geometry, and
embed it in the membranes and five-branes of the eleven-dimensional
supergravity. We explicitly show that the solutions preserve eight
supersymmetries. Upon compactification on a circle, we find fully localized
intersecting brane systems. We also discuss the T-dual and the decoupling
limits of the solutions.


  We derive generalization bounds for learning algorithms based on their
robustness: the property that if a testing sample is "similar" to a training
sample, then the testing error is close to the training error. This provides a
novel approach, different from the complexity or stability arguments, to study
generalization of learning algorithms. We further show that a weak notion of
robustness is both sufficient and necessary for generalizability, which implies
that robustness is a fundamental property for learning algorithms to work.


  The relativistic expression for the $n$-th order moment of the nuclear charge
density is presented. For the mean square radius(msr) of the nuclear charge
density, the non-relativistic expression, which is equivalent to the
relativistic one, is also derived consistently up to $1/M^2$ with use of the
Foldy-Wouthuysen transformation. The difference between the relativistic and
non-relativistic expressions for the msr of the point proton density is also
discussed. The $n(\ge 4)$-th order moment of the nuclear charge density depends
on the point neutron density. The 4-th order moment yields a useful information
on the msr of the point neutron density, and is expected to play an important
role in electron scattering off neutron-rich nuclei.


  Precision optical spectroscopy of exotic ions reveals accurate information
about nuclear properties such as charge radii and magnetic and quadrupole
moments. Thorium ions exhibit unique nuclear properties with high relevance for
testing symmetries of nature. We report loading and trapping of single
$^{232}$Th$^+$ ions in a linear Paul trap, embedded into and sympathetically
cooled by small crystals of trapped $^{40}$Ca$^+$ ions. Trapped Th ions are
identified in a non-destructive manner from the voids in the laser-induced Ca
fluorescence pattern emitted by the crystal, and alternatively, by means of a
time-of-flight signal when extracting ions from the Paul trap and steering them
into an external detector. We have loaded and handled a total of 231 individual
Th ions. We reach a time-of-flight detection efficiency of $\gtrsim 95\, \%$,
consistent with the quantum efficiency of the detector. The sympathetic cooling
technique is expected to be applicable for other isotopes and various charge
states of Th e.g., for future studies of $^{229m}$Th.


  A growing body of evidence suggests that part of, if not all, scattering
regions of active galactic nuclei (AGNs) are clumpy. Hence. in this paper, we
run radiative transfer models in the optical/UV for a variety of AGN
reprocessing regions with different distributions of clumpy scattering media.
We use the latest version of the Monte Carlo code STOKES presented in the first
two papers of this series to model AGN reprocessing regions of increasing
morphological complexity. We replace previously uniform-density media with up
to thousands of constant-density clumps. We couple a continuum source to
fragmented equatorial scattering regions, polar outflows, and toroidal,
obscuring dust regions and investigate a wide range of geometries. We also
consider different levels of fragmentation in each scattering region to
evaluate importance of fragmentation for the net polarization of the AGN. We
find that, in comparison with uniform-density models, equatorial distributions
of gas and dust clouds result in grayer spectra, and show a decrease of the net
polarization percentage at all lines of sight. The resulting polarization
position angle depends on the morphology of the clumpy structure, with extended
tori favoring parallel polarization while compact tori produce orthogonal
polarization position angles. In the case of polar scattering regions,
fragmentation increases the net polarization unless the cloud filling factor is
small. A complete set of AGN models constructed from the individual, fragmented
regions is investigated. Our modeling shows that the introduction of fragmented
dusty tori significantly alters the resulting net polarization of an AGN.
Comparison of our models to polarization observations of large AGN samples
greatly favors geometrically compact clumpy tori over extended ones.


  In three seasons of 2015-2018 we carried out a series of visible and near
infrared (NIR) photometry of SU Aur. In course of this photometric monitoring
we detected an event of a deep fading of the star in spring of 2018. In this
paper we present preliminary analysis of our photometry.


  This work focuses on the space-time reduced-order modeling (ROM) method for
solving large-scale uncertainty quantification (UQ) problems with multiple
random coefficients. In contrast with the traditional space ROM approach, which
performs dimension reduction in the spatial dimension, the space-time ROM
approach performs dimension reduction on both the spatial and temporal domains,
and thus enables accurate approximate solutions at a low cost. We incorporate
the space-time ROM strategy with various classical stochastic UQ propagation
methods such as stochastic Galerkin and Monte Carlo. Numerical results
demonstrate that our methodology has significant computational advantages
compared to state-of-the-art ROM approaches. By testing the approximation
errors, we show that there is no obvious loss of simulation accuracy for
space-time ROM given its high computational efficiency.


  This article is a review of modern approaches to gravity that treat the
gravitational interaction as a type of gauge theory. The purpose of the article
is twofold. First, it is written in a colloquial style and is intended to be a
pedagogical introduction to the gauge approach to gravity. I begin with a
review of the Einstein-Cartan formulation of gravity, move on to the
Macdowell-Mansouri approach, then show how gravity can be viewed as the
symmetry broken phase of an (A)dS-gauge theory. This covers roughly the first
half of the article. Armed with these tools, the remainder of the article is
geared toward new insights and new lines of research that can be gained by
viewing gravity from this perspective. Drawing from familiar concepts from the
symmetry broken gauge theories of the standard model, we show how the
topological structure of the gauge group allows for an infinite class of new
solutions to the Einstein-Cartan field equations that can be thought of as
degenerate ground states of the theory. We argue that quantum mechanical
tunneling allows for transitions between the degenerate vacua. Generalizing the
tunneling process from a topological phase of the gauge theory to an arbitrary
geometry leads to a modern reformulation of the Hartle-Hawking "no boundary"
proposal.


  We apply the extended (statistically-consistent, SGA) Gutzwiller-type
approach to the periodic Anderson model (PAM) in an applied magnetic field and
in the strong correlation limit. The finite-U corrections are included
systematically by transforming PAM into the form with Kondo-type interaction
and residual hybridization, appearing both at the same time. This effective
Hamiltonian represents the essence of \textit{Anderson-Kondo lattice model}. We
show that in ferromagnetic phases the low-energy single-particle states are
strongly affected by the presence of the applied magnetic field. We also find
that for large values of hybridization strength the system enters the so-called
\textit{locked heavy fermion state}. In this state the chemical potential lies
in the majority-spin hybridization gap and as a consequence, the system
evolution is insensitive to further increase of the applied field. However, for
a sufficiently strong magnetic field, the system transforms from the locked
state to the fully spin-polarized phase. This is accompanied by a metamagnetic
transition, as well as by drastic reduction of the effective mass of
quasiparticles. In particular, we observe a reduction of effective mass
enhancement in the majority-spin subband by as much as 20% in the fully
polarized state. The findings are consistent with experimental results for
Ce$_x$La$_{1-x}$B$_6$ compounds. The mass enhancement for the spin-minority
electrons may also diminish with the increasing field, unlike for the
quasiparticles states in a single narrow band in the same limit of strong
correlations.


  The evolution of a Universe modelled as a mixture of a Chaplygin gas and
radiation is determined by taking into account irreversible processes. This
mixture could interpolate periods of a radiation dominated, a matter dominated
and a cosmological constant dominated Universe. The results of a Universe
modelled by this mixture are compared with the results of a mixture whose
constituents are radiation and quintessence. Among other results it is shown
that: (a) for both models there exists a period of a past deceleration with a
present acceleration; (b) the slope of the acceleration of the Universe
modelled as a mixture of a Chaplygin gas with radiation is more pronounced than
that modelled as a mixture of quintessence and radiation; (c) the energy
density of the Chaplygin gas tends to a constant value at earlier times than
the energy density of quintessence does; (d) the energy density of radiation
for both mixtures coincide and decay more rapidly than the energy densities of
the Chaplygin gas and of quintessence.


  A key advantage of isogeometric discretizations is their accurate and
well-behaved eigenfrequencies and eigenmodes. For degree two and higher,
however, optical branches of spurious outlier frequencies and modes may appear
due to boundaries or reduced continuity at patch interfaces. In this paper, we
introduce a variational approach based on perturbed eigenvalue analysis that
eliminates outlier frequencies without negatively affecting the accuracy in the
remainder of the spectrum and modes. We then propose a pragmatic iterative
procedure that estimates the perturbation parameters in such a way that the
outlier frequencies are effectively reduced. We demonstrate that our approach
allows for a much larger critical time-step size in explicit dynamics
calculations. In addition, we show that the critical time-step size obtained
with the proposed approach does not depend on the polynomial degree of spline
basis functions.


  The phase diagram of the half-filled spinless Holstein model for electrons
interacting with quantum phonons is derived in three dimensions extending at
finite temperature $T$ a variational approach introduced for the
one-dimensional T=0 case. Employing the variational scheme, the spectral and
optical properties of the system are evaluated in the different regimes that
characterize the normal and ordered state. The effects of the charge-ordering
($CO$) induce a transfer of spectral weight from low to high energies in the
conductivity spectra, as the temperature decreases or the strength of the
electron-phonon ($el-ph$) interaction increases. The inclusion of effects of
lattice fluctuations is able to smooth the inverse square-root singularity
expected for the case of the mean-field approach and determines a subgap tail
absorption. Moreover, in the weak to intermediate coupling regime, a
two-component structure is obtained within the $CO$ phase at low frequency: the
remnant Drude-like term and the incipient absorption band centered around the
gap energy.


  The longitudinal and Hall resistances have recently been measured for quantum
Hall bilayers at total filling $\nu=1$ in the superfluid state with interlayer
pairing, both for currents flowing parallel to one another and for
"counterflowing" currents in the two layers. Here I examine the contribution to
these resistances from the motion of unpaired vortices in these systems,
developing some possible explanations of various qualitative features of these
data.


  I shortly review the present status of the theoretical calculations of
eps'/eps and the comparison with the present experimental results. I discuss
the role of higher order chiral corrections and in general of non-factorizable
contributions for the explanation of the Delta I = 1/2 selection rule and
direct CP violation in kaon decays. Still lacking satisfactory lattice
calculations, analytic methods and phenomenological approaches are helpful in
understanding correlations among theoretical effects and experimental data.
Substantial progress from lattice QCD is expected in the coming years.


  We investigate the nonlinear dynamics of a damped Peyrard-Bishop DNA model
taking into account long-range interactions with distance dependence |l|^-s on
the elastic coupling constant between different DNA base pairs. Considering
both Stokes and long-range hydrodynamical damping forces, we use the discrete
difference operator technique and show in the short wavelength modes that the
lattice equation can be governed by the complex Ginzburg-Landau equation. We
found analytically that the technique leads to the correct expression for the
breather soliton parameters. We found that the viscosity makes the amplitude of
the breather to damp out. We compare the approximate analytic results with
numerical simulations for the value s = 3 (dipole-dipole interactions).


  Gravitational waves emitted by high redshift sources propagate through
various epochs of the Universe including the current era of measurable,
accelerated expansion. Historically, the calculation of gravitational wave
power on cosmological backgrounds is based on various simplifications,
including a $1/r$-expansion and the use of an algebraic projection to retrieve
the radiative degrees of freedom. On a de Sitter spacetime, recent work has
demonstrated that many of these calculational techniques and approximations do
not apply. Here we calculate the power emitted by a binary system on a de
Sitter background using techniques tailored to de Sitter spacetime. The common
expression for the power radiated by this source in an FLRW spacetime,
calculated using far wave-zone techniques, gives the same expression as the
late time expansion specialized to the de Sitter background in the
high-frequency approximation.


  We report the discovery of a giant out-of-plane coercivity in the Fe-doped
Mn3Sn single crystals. The compound of Mn2.42Fe0.58Sn exhibits a series of
magnetic transitions accompanying with large magnetic anisotropy and electric
transport properties. Compared with the ab-plane easy axis in Mn3Sn, it
switches to the c-axis in Mn2.42Fe0.58Sn, producing a sufficiently large
uniaxial anisotropy. At 2 K, a giant out-of-plane coercivity (Hc) up to 3 T was
observed, which originates from the large uniaxial magnetocrystalline
anisotropy. The modified Sucksmith-Thompson method was used to determine the
values of the second-order and the fourth-order magnetocrystalline anisotropy
constants K1 and K2, resulting in values of 6.0 * 104 J/m3 and 4.1 * 105 J/m3
at 2 K, respectively. Even though the Curie temperature (TC) of 200 K for
Mn2.42Fe0.58Sn is not high enough for direct application, our research presents
a valuable case study of a typical uniaxial anisotropy material.


  We report the optical discovery of the companion to the 2 M_sun millisecond
pulsar PSR J1614-2230. The optical colors show that the 0.5 M_sun companion is
a 2.2 Gyr old He-CO white dwarf. We infer that $\dot{M}$ during the accretion
phase is <10^{-2}\dot{M}_{edd}. We show that the pulsar was born with a spin
close to its current value, well below the rebirth line. The spin-down
parameters, the mass of the pulsar, and the age of the system challenge the
simple recycling model for the formation of millisecond pulsars.


  We introduce new zeta functions related to an endomorphism $\phi$ of a
discrete group $\Gamma$. They are of two types: counting numbers of fixed
($\rho\sim \rho\circ\phi^n$) irreducible representations for iterations of
$\phi$ from an appropriate dual space of $\Gamma$ and counting Reidemeister
numbers $R(\phi^n)$ of different compactifications. Many properties of these
functions and their coefficients are obtained. In many cases it is proved that
these zeta functions coincide. The Gauss congruences are proved. Useful
asymptotic formulas for the zeta functions are found. Rationality is proved for
some examples, which give also the first counterexamples simultaneously for
TBFT ($R(\phi)$=the number of fixed irreducible unitary representations) and
TBFT$_f$ ($R(\phi)$=the number of fixed irreducible unitary finite-dimensional
representations) for an automorphism $\phi$ with $R(\phi)<\infty$.


  Generalizing the work of Kobayashi and the second author for elliptic curves
with supersingular reduction at the prime $p$, B\"uy\"ukboduk and Lei
constructed multi-signed Selmer groups over the cyclotomic
$\mathbb{Z}_p$-extension of a number field $F$ for more general non-ordinary
motives. In particular, their construction applies to abelian varieties over
$F$ with good supersingular reduction at all the primes of $F$ above $p$. In
this article, we scrutinize the case in which $F$ is imaginary quadratic, and
prove a control theorem (that generalizes Kim's control theorem for elliptic
curves) of multi-signed Selmer groups of non-ordinary motives over the maximal
abelian pro-$p$ extension of $F$ that is unramified outside $p$, which is the
$\mathbb{Z}_p^2$-extension of $F$. We apply it to derive a sufficient condition
when these multi-signed Selmer groups are cotorsion over the corresponding
two-variable Iwasawa algebra. Furthermore, we compare the Iwasawa
$\mu$-invariants of multi-signed Selmer groups over the
$\mathbb{Z}_p^2$-extension for two such representations which are congruent
modulo $p$.


  We study Swendsen--Wang dynamics for the critical $q$-state Potts model on
the square lattice. For $q=2,3,4$, where the phase transition is continuous,
the mixing time $t_{\textrm{mix}}$ is expected to obey a universal power-law
independent of the boundary conditions. On the other hand, for large $q$, where
the phase transition is discontinuous, the authors recently showed that
$t_{\textrm{mix}}$ is highly sensitive to boundary conditions:
$t_{\textrm{mix}} \geq \exp(cn)$ on an $n\times n$ box with periodic boundary,
yet under free or monochromatic boundary conditions, $t_{\textrm{mix}}
\leq\exp(n^{o(1)})$.
  In this work we classify this effect under boundary conditions that
interpolate between these two (torus vs. free/monochromatic). Specifically, if
one of the $q$ colors is red, mixed boundary conditions such as
red-free-red-free on the 4 sides of the box induce $t_{\textrm{mix}} \geq
\exp(cn)$, yet Dobrushin boundary conditions such as red-red-free-free, as well
as red-periodic-red-periodic, induce sub-exponential mixing.


  Energy-based ultrasound elastography techniques minimize a regularized cost
function consisting of data and continuity terms to obtain local displacement
estimates based on the local time-delay estimation (TDE) between
radio-frequency (RF) frames. The data term associated with the existing
techniques takes only the amplitude similarity into account and hence is not
sufficiently robust to the outlier samples present in the RF frames under
consideration. This drawback creates noticeable artifacts in the strain image.
To resolve this issue, we propose to formulate the data function as a linear
combination of the amplitude and gradient similarity constraints. We estimate
the adaptive weight concerning each similarity term following an iterative
scheme. Finally, we optimize the non-linear cost function in an efficient
manner to convert the problem to a sparse system of linear equations which are
solved for millions of variables. We call our technique rGLUE: robust data term
in GLobal Ultrasound Elastography. rGLUE has been validated using simulation,
phantom, in vivo liver, and breast datasets. In all of our experiments, rGLUE
substantially outperforms the recent elastography methods both visually and
quantitatively. For simulated, phantom, and in vivo datasets, respectively,
rGLUE achieves 107%, 18%, and 23% improvements of signal-to-noise ratio (SNR)
and 61%, 19%, and 25% improvements of contrast-to-noise ratio (CNR) over GLUE,
a recently-published elastography algorithm.


  Cosmological birefringence, a rotation by an angle $\alpha$ of the
polarization of photons as they propagate over cosmological distances, is
constrained by the cosmic microwave background (CMB) to be
$|\alpha|\lesssim1^\circ$ ($1\sigma$) out to redshifts $z\simeq1100$ for a
rotation that is uniform across the sky. However, the rotation angle
$\alpha(\theta,\phi)$ may vary as a function of position $(\theta,\phi)$ on the
sky. Here I discuss how a position-dependent rotation can be sought in current
and future AGN data. An upper limit $\VEV{\alpha^2}^{1/2} \lesssim 3.7^\circ$
to the scatter in the position-angle--polarization offsets in a sample of only
N=9 AGN already constrains the rotation spherical-harmonic coefficients to
$(4\pi)^{-1/2} \alpha_{lm}\lesssim 3.7^\circ$ and constrains the power spectrum
for $\alpha$ in models where it is a stochastic field. Future constraints can
be improved with more sources and by analyzing well-mapped sources with a
tensor-harmonic decomposition of the polarization analogous to that used in CMB
polarization and weak gravitational lensing.


  In null electromagnetic fields the electric and the magnetic field lines
evolve like unbreakable elastic filaments in a fluid flow. In particular, their
topology is preserved for all time. We prove that for every link $L$ there is
such an electromagnetic field that satisfies Maxwell's equations in free space
and that has closed electric and magnetic field lines in the shape of $L$ for
all time.


  We consider an addition of the term which is a square of the scalar curvature
to the Einstein-Hilbert action. Under this generalized action, we attempt to
explain i) the flat rotation curves observed in spiral galaxies, which is
usually attributed to the existence of dark matter, and ii) the contradicting
observations of uniform cosmic microwave background and non-uniform galaxy
distributions against redshift. For the former, we attain the flatness of
velocities, although the magnitudes remain about half of the observations. For
the latter, we obtain a solution with oscillating Hubble parameter under
uniform mass distributions. This solution leads to several peaks of galaxy
number counts as a function of redshift with the first peak corresponding to
the Great Wall.


  The main ideas behind the classical multivariate logistic regression model
make sense when translated to the functional setting, where the explanatory
variable $X$ is a function and the response $Y$ is binary. However, some
important technical issues appear (or are aggravated with respect to those of
the multivariate case) due to the functional nature of the explanatory
variable. First, the mere definition of the model can be questioned: while most
approaches so far proposed rely on the $L_2$-based model, we suggest an
alternative (in some sense, more general) approach, based on the theory of
Reproducing Kernel Hilbert Spaces (RKHS). The validity conditions of such
RKHS-based model, as well as its relation with the $L_2$-based one are
investigated and made explicit in two formal results. Some relevant particular
cases are considered as well. Second we show that, under very general
conditions, the maximum likelihood (ML) of the logistic model parameters fail
to exist in the functional case. Third, on a more positive side, we suggest an
RKHS-based restricted version of the ML estimator. This is a methodological
paper, aimed at a better understanding of the functional logistic model, rather
than focusing on numerical and practical issues.


  We ask the question whether for a given unitary representation $U$ the
associated operator $\rho_{U}\in\operatorname{Mor}(U,U^{c\, c})$ has spectrum
invariant under inversion -- in this case we say that $\rho_{U}$ has symmetric
eigenvalues. This does not have to be the case. However, we give affirmative
answer whenever a certain condition on the growth of dimensions of irreducible
subrepresentations of tensor powers of $U$ is imposed. This condition is
satisfied whenever $\widehat{\mathbb{G}}$ is of subexponential growth.


  This article is based on a talk given by one of us (EVI) at the conference
``StatPhys-Taipei-1997''. It overviews the exact results in the theory of the
sandpile model and discusses shortly yet unsolved problem of calculation of
avalanche distribution exponents. The key ingredients include the analogy with
the critical reaction-diffusion system, the spanning tree representation of
height configurations and the decomposition of the avalanche process into waves
of topplings.


  We consider polynomials that are defined as Wronskians of certain sets of
Hermite polynomials. Our main result is a recurrence relation for these
polynomials in terms of those of one or two degrees smaller, which generalizes
the well-known three term recurrence relation for Hermite polynomials. The
polynomials are defined using partitions of natural numbers, and the
coefficients in the recurrence relation can be expressed in terms of the number
of standard Young tableaux of these partitions. Using the recurrence relation,
we provide another recurrence relation and show that the average of the
considered polynomials with respect to the Plancherel measure is very simple.
Furthermore, we show that some existing results in the literature are easy
corollaries of the recurrence relation.


  In this paper we present studies of the I-V characteristics of CdZnTe
detectors with Pt contacts fabricated from high-resistivity single crystals
grown by the high-pressure Brigman process. We have analyzed the experimental
I-V curves using a model that approximates the CZT detector as a system
consisting of a reversed Schottky contact in series with the bulk resistance.
Least square fits to the experimental data yield 0.78-0.79 eV for the Pt-CZT
Schottky barrier height, and <20 V for the voltage required to deplete a 2 mm
thick CZT detector. We demonstrate that at high bias the thermionic current
over the Schottky barrier, the height of which is reduced due to an interfacial
layer between the contact and CZT material, controls the leakage current of the
detectors. In many cases the dark current is not determined by the resistivity
of the bulk material, but rather the properties of the contacts; namely by the
interfacial layer between the contact and CZT material.


  We explain the mixed Hodge structure (MHS) on the complement of the
generalized theta divisor of a curve in its generalized jacobians. Our approach
considers the generalized jacobian via degeneration of smooth jacobians as a
determinantal varieties. We make the question if the MHS can be explained by
graphs or their degenerations.


  We study the properly discontinuous and isometric actions on the unit sphere
of infinite dimensional Hilbert spaces and we get some new examples of Hilbert
manifold with costant positive sectional curvature. We prove some necessary
conditions for a group to act isometrically and properly discontinuously and in
the case of finitely generated Abelian groups, the necessary and sufficient
conditions are given.


  Wikidata is a free and open knowledge base from the Wikimedia Foundation,
that not only acts as a central storage of structured data for other projects
of the organization, but also for a growing array of information systems,
including search engines. Like Wikipedia, Wikidata's content can be created and
edited by anyone; which is the main source of its strength, but also allows for
malicious users to vandalize it, risking the spreading of misinformation
through all the systems that rely on it as a source of structured facts. Our
task at the WSDM Cup 2017 was to come up with a fast and reliable prediction
system that narrows down suspicious edits for human revision. Elaborating on
previous works by Heindorf et al. we were able to outperform all other
contestants, while incorporating new interesting features, unifying the
programming language used to only Python and refactoring the feature extractor
into a simpler and more compact code base.


  We study the statistical properties of two hard spheres in a two dimensional
rectangular box. In this system, the relation like Van der Waals equation loop
is obtained between the width of the box and the pressure working on side
walls. The auto-correlation function of each particle's position is calculated
numerically. By this calculation near the critical width, the time at which the
correlation become zero gets longer according to the increase of the height of
the box. Moreover, fast and slow relaxation processes like $\alpha$ and $\beta$
relaxations observed in supper cooled liquid are observed when the height of
the box is sufficiently large. These relaxation processes are discussed with
the probability distribution of relative position of two particles.


  The mass spectra and wave functions for the doubly heavy baryons are computed
under the picture that the two heavy quarks inside a doubly heavy baryon, such
as two $c$-quarks in $\Xi_{cc}$, combine into a heavy `diquark core' in color
anti-triplet firstly, then the diquark core turns into a color-less doubly
heavy baryon via combining the light $q$-quark inside the baryon. Namely both
of the combinations, the two heavy quarks inside the baryon into a diquark core
in color anti-triplet and the heavy diquark core with the light quark into the
baryon, are depicted by relativistic Bethe-Salpeter equations (BSEs) with an
accordingly QCD inspired kernel respectively, although in the paper only the
heavy diquark cores with the quantum numbers $J^P=1^+$ are considered. Since
the `second combination' is of the heavy diquark core and the light quark, so
the structure effect of the diquark core to the relevant kernel of the BSE is
specially considered in terms of the diquark-core wave functions. The mass
spectra and wave functions for the `low-laying' doubly heavy baryons in the
flavors $(ccq)$, $(bcq)$ and $(bbq)$ and in the quantum numbers
$J^P=\frac{1}{2}^+$, $J^P=\frac{3}{2}^+$, achieved by solving the equations
under the so-called instantaneous approximation, are presented properly and
some comparisons with the others' results under different approaches in the
literature are made.


  Interpolating functional method is a powerful tool for studying the behavior
of a quantity in the intermediate region of the parameter space of interest by
using its perturbative expansions at both ends. Recently several interpolating
functional methods have been proposed, in addition to the well-known Pade
approximant, namely the "Fractional Power of Polynomial" (FPP) and the
"Fractional Power of Rational functions" (FPR) methods. Since combinations of
these methods also give interpolating functions, we may end up with multitudes
of the possible approaches. So a criterion for choosing an appropriate
interpolating function is very much needed. In this paper, we propose reference
quantities which can be used for choosing a good interpolating function. In
order to validate the prescription based on these quantities, we study the
degree of correlation between "the reference quantities" and the "actual degree
of deviation between the interpolating function and the true function" in
examples where the true functions are known.


  The volume of open-source biomedical data has been essential to the
development of various spheres of the healthcare community since more `free'
data can provide individual researchers more chances to contribute. However,
institutions often hesitate to share their data with the public due to the risk
of data exploitation by unauthorized third parties for another commercial usage
(e.g., training AI models). This phenomenon might hinder the development of the
whole healthcare research community. To address this concern, we propose a
novel approach termed `unlearnable biomedical image' for protecting biomedical
data by injecting imperceptible but delusive noises into the data, making them
unexploitable for AI models. We formulate the problem as a bi-level
optimization and propose three kinds of anti-learning perturbation generation
approaches to solve the problem. Our method is an important step toward
encouraging more institutions to contribute their data for the long-term
development of the research community.


  We study a problem of optimal information gathering from multiple data
providers that need to be incentivized to provide accurate information. This
problem arises in many real world applications that rely on crowdsourced data
sets, but where the process of obtaining data is costly. A notable example of
such a scenario is crowd sensing. To this end, we formulate the problem of
optimal information gathering as maximization of a submodular function under a
budget constraint, where the budget represents the total expected payment to
data providers. Contrary to the existing approaches, we base our payments on
incentives for accuracy and truthfulness, in particular, {\em peer-prediction}
methods that score each of the selected data providers against its best peer,
while ensuring that the minimum expected payment is above a given threshold. We
first show that the problem at hand is hard to approximate within a constant
factor that is not dependent on the properties of the payment function.
However, for given topological and analytical properties of the instance, we
construct two greedy algorithms, respectively called PPCGreedy and
PPCGreedyIter, and establish theoretical bounds on their performance w.r.t. the
optimal solution. Finally, we evaluate our methods using a realistic crowd
sensing testbed.


  VDJ rearrangement and somatic hypermutation work together to produce
antibody-coding B cell receptor (BCR) sequences for a remarkable diversity of
antigens. It is now possible to sequence these BCRs in high throughput;
analysis of these sequences is bringing new insight into how antibodies
develop, in particular for broadly-neutralizing antibodies against HIV and
influenza. A fundamental step in such sequence analysis is to annotate each
base as coming from a specific one of the V, D, or J genes, or from an
N-addition (a.k.a. non-templated insertion). Previous work has used simple
parametric distributions to model transitions from state to state in a hidden
Markov model (HMM) of VDJ recombination, and assumed that mutations occur via
the same process across sites. However, codon frame and other effects have been
observed to violate these parametric assumptions for such coding sequences,
suggesting that a non-parametric approach to modeling the recombination process
could be useful. In our paper, we find that indeed large modern data sets
suggest a model using parameter-rich per-allele categorical distributions for
HMM transition probabilities and per-allele-per-position mutation
probabilities, and that using such a model for inference leads to significantly
improved results. We present an accurate and efficient BCR sequence annotation
software package using a novel HMM "factorization" strategy. This package,
called partis (https://github.com/psathyrella/partis/), is built on a new
general-purpose HMM compiler that can perform efficient inference given a
simple text description of an HMM.


  The concept of QCD sum rules is extended to bound states composed of
particles with finite mass such as scalar quarks or strange quarks. It turns
out that mass corrections become important in this context. The number of
relevant corrections is analyzed in a systematic discussion of the IR- and
UV-divergencies, leading in general to a finite number of corrections. The
results are demonstrated for a system of two massless quarks and two heavy
scalar quarks.


  In the realm of medical imaging, precise segmentation of stroke lesions from
brain MRI images stands as a critical challenge with significant implications
for patient diagnosis and treatment. Addressing this, our study introduces an
innovative approach using a Fuzzy Information Seeded Region Growing (FISRG)
algorithm. Designed to effectively delineate the complex and irregular
boundaries of stroke lesions, the FISRG algorithm combines fuzzy logic with
Seeded Region Growing (SRG) techniques, aiming to enhance segmentation
accuracy.
  The research involved three experiments to optimize the FISRG algorithm's
performance, each focusing on different parameters to improve the accuracy of
stroke lesion segmentation. The highest Dice score achieved in these
experiments was 94.2\%, indicating a high degree of similarity between the
algorithm's output and the expert-validated ground truth. Notably, the best
average Dice score, amounting to 88.1\%, was recorded in the third experiment,
highlighting the efficacy of the algorithm in consistently segmenting stroke
lesions across various slices.
  Our findings reveal the FISRG algorithm's strengths in handling the
heterogeneity of stroke lesions. However, challenges remain in areas of abrupt
lesion topology changes and in distinguishing lesions from similar intensity
brain regions. The results underscore the potential of the FISRG algorithm in
contributing significantly to advancements in medical imaging analysis for
stroke diagnosis and treatment.


  What happens to the entropy increase principle as the Universe evolve to form
the big-crunch singularity? What happens to the uncertainity relations along
the process of gravitational collapses? What is the quantum mechanical
description of a Radon atom in a rigid box when the distance of consecutive
nodes and antinodes of $\psi$ is equal to or less than the diameter of the
atom? What is the position-space wave function of two finite volume massive
bosons if we take contact interaction into account? How a photon produce
electron-positron pair with finite volume concentrate rest masses? What are the
charges of the electron-positron pairs forming loops in the vacuum? How two
particles with three-momentums $k_1, k_2$ $(k_1 \neq k_2)$ produced to form a
loop at a space-time point always arrive at another spacial point
simultaneously? What is the microscopic explanation in terms of particle
exchanges of the force in the Casimir effect? What is the mechanism of the
collapse of the momentum-space wave function of a particle knocking out an
elctron from an atom? What is meant by $|\Psi> = {c_1 (t)}|\Psi_{U^{238}}> +
{c_2 (t)}|\Psi_{Th^{234}}> ~?$ Quantum mechanically the region between the
rigid walls (which is equiprobable in classical mechanics) is non-homogeneous
for a particle in a rigid box ! The large scale structure of the Universe is
homogeneous.


  Cactus networks were introduced by Lam as a generalization of planar
electrical networks. He defined a map from these networks to the Grassmannian
Gr($n+1,2n$) and showed that the image of this map, $\mathcal X_n$ lies inside
the totally nonnegative part of this Grassmannian. In this paper, we show that
$\mathcal X_n$ is exactly the elements of Gr($n+1,2n$) that are both totally
nonnegative and isotropic for a particular skew-symmetric bilinear form. For
certain classes of cactus networks, we also explicitly describe how to turn
response matrices and effective resistance matrices into points of Gr($n+1,2n$)
given by Lam's map. Finally, we discuss how our work relates to earlier studies
of total positivity for Lagrangian Grassmannians.


  Device-free context awareness is important to many applications. There are
two broadly used approaches for device-free context awareness, i.e. video-based
and radio-based. Video-based applications can deliver good performance, but
privacy is a serious concern. Radio-based context awareness has drawn
researchers attention instead because it does not violate privacy and radio
signal can penetrate obstacles. Recently, deep learning has been introduced
into radio-based device-free context awareness and helps boost the recognition
accuracy. The present works design explicit methods for each radio based
application. They also use one additional step to extract features before
conducting classification and exploit deep learning as a classification tool.
The additional initial data processing step introduces unnecessary noise and
information loss. Without initial data processing, it is, however, challenging
to explore patterns of raw signals. In this paper, we are the first to propose
an innovative deep learning based general framework for both signal processing
and classification. The key novelty of this paper is that the framework can be
generalised for all the radio-based context awareness applications. We also
eliminate the additional effort to extract features from raw radio signals. We
conduct extensive evaluations to show the superior performance of our proposed
method and its generalisation.


  Context: Most approaches to automated white-box testing consider the client
side and the server side of a web application in isolation from each other.
Such testers lack a whole-program perspective on the web application under
test.
  Inquiry: We hypothesise that an additional whole-program perspective would
enable the tester to discover which server side errors can be triggered by an
actual end user accessing the application through the client, and which ones
can only be triggered in hypothetical scenarios.
  Approach: In this paper, we explore the idea of employing such a
whole-program perspective in testing. To this end, we develop , a novel
concolic tester which operates on full-stack JavaScript web applications, where
both the client and the server side are JavaScript processes communicating via
asynchronous messages -- as enabled by the WebSocket or Socket.IO-libraries.
  Knowledge: We find that the whole-program perspective enables discerning
high-priority errors, which are reachable from a particular client, from
low-priority errors, which are not accessible through the tested client.
Another benefit of the perspective is that it allows the automated tester to
construct practical, step-by-step scenarios for triggering server side errors
from the end user's perspective.
  Grounding: We apply on a collection of web applications to evaluate how
effective testing is in distinguishing between high- and low-priority errors.
The results show that correctly classifies the majority of server errors.
  Importance: This paper demonstrates the feasibility of testing as a novel
approach for automatically testing web applications. Classifying errors as
being of high or low importance aids developers in prioritising bugs that might
be encountered by users, and postponing the diagnosis of bugs that are less
easily reached.


  The development of optical metrology suited to ultrafast lasers has played a
key role in the progress of these light sources in the last few decades.
Measurement techniques providing the complete $E$-field of ultrashort laser
beams in both time and space are now being developed. Yet, they had so far not
been applied to the most powerful ultrashort lasers, which reach the PetaWatt
range by pushing the Chirped Pulse Amplification scheme to its present
technical limits. This situation left doubts on their actual performance, and
in particular on the peak intensity they can reach at focus. In this article we
present the first complete spatio-temporal characterization of a PetaWatt
femtosecond laser operating at full intensity, the BELLA laser, using two
recently-developed independent measurement techniques. Our results demonstrate
that, with adequate optimization, the CPA technique is still suitable at these
extreme scales, i.e., it is not inherently limited by spatio-temporal
couplings. We also show how these measurements provide unprecedented insight
into the physics and operation regime of such laser systems.


  This paper gives an explicit construction of the Tate resolution of sheaves
arising from the d-fold Veronese embedding of P^n. Our description involves the
Bezoutian of n+1 homogenous forms of degree d in n+1 variables. We give
applications to duality theorems, including Koszul duality.


  We study the degenerate linear Boltzmann equation inside a bounded domain
with the Maxwell and the Cercignani-Lampis boundary conditions, two
generalizations of the diffuse reflection, with variable temperature. This
includes a model of relaxation towards a space-dependent steady state. For both
boundary conditions, we prove for the first time the existence of a steady
state and a rate of convergence towards it without assumptions on the
temperature variations. Our results for the Cercignani-Lampis boundary
condition make also no hypotheses on the accommodation coefficients. The proven
rate is exponential when a control condition on the degeneracy of the collision
operator is satisfied, and only polynomial when this assumption is not met, in
line with our previous results regarding the free-transport equation. We also
provide a precise description of the different convergence rates, including
lower bounds, when the steady state is bounded. Our method yields constructive
constants.


  As the communication industry has connected distant corners of the globe
using advances in network technology, intruders or attackers have also
increased attacks on networking infrastructure commensurately. System
administrators can attempt to prevent such attacks using intrusion detection
tools and systems. There are many commercially available signature-based
Intrusion Detection Systems (IDSs). However, most IDSs lack the capability to
detect novel or previously unknown attacks. A special type of IDSs, called
Anomaly Detection Systems, develop models based on normal system or network
behavior, with the goal of detecting both known and unknown attacks. Anomaly
detection systems face many problems including high rate of false alarm,
ability to work in online mode, and scalability. This paper presents a
selective survey of incremental approaches for detecting anomaly in normal
system or network traffic. The technological trends, open problems, and
challenges over anomaly detection using incremental approach are also
discussed.


  The supersymmetric model developed by Witten to study the equivariant
cohomology of a manifold with an isometric circle action is derived from the
BRST quantization of a simple classical model. The gauge-fixing process is
carefully analysed, and demonstrates that different choices of gauge-fixing
fermion can lead to different quantum theories.


  We propose that spin glasses can exist in equally probable superposition
states (SSs) comprising potential configurations. Employing the Edward-Anderson
(EA) order parameter and magnetization, we establish a classification scheme
for these SSs based on their contribution to discerning magnetic order
(disorder), such as SG, ferromagnetic (FM), and paramagnetic (PM) phases. We
also encompass various system sizes and investigate the entanglement properties
of these phase-dependent SSs using the negativity measure. Our analysis reveals
that the SG order parameter can be employed to determine the entanglement
characteristics of magnetically ordered (disordered) phases, and vice versa,
with negativity indicating the presence of magnetic order. Specifically, we
examine the relationship between negativity and susceptibility in spin-glass
systems. Our findings provide further insight into the role of quantum
superposition in spin glasses and quantum magnets.


  We present ab initio studies of photoelectron spectra for above threshold
detachment (ATD) of F$^-$ anions in short, 1300 nm and 1800 nm laser pulses. We
identify and assess the importance of electron rescattering in strong-field
photodetachment of a negative ion through comparison with an analytic,
Keldysh-type approach, demonstrating the capability of ab-initio computation in
the challenging near-IR regime. We further assess the influence of the strong
electron correlation on the photodetachment.


  The paper presents the graph Fourier transform (GFT) of a signal in terms of
its spectral decomposition over the Jordan subspaces of the graph adjacency
matrix $A$. This representation is unique and coordinate free, and it leads to
unambiguous definition of the spectral components ("harmonics") of a graph
signal. This is particularly meaningful when $A$ has repeated eigenvalues, and
it is very useful when $A$ is defective or not diagonalizable (as it may be the
case with directed graphs). Many real world large sparse graphs have defective
adjacency matrices. We present properties of the GFT and show it to satisfy a
generalized Parseval inequality and to admit a total variation ordering of the
spectral components. We express the GFT in terms of spectral projectors and
present an illustrative example for a real world large urban traffic dataset.


  The morphology and the microscopic internal dynamics of a bidimensional gel
formed by spontaneous aggregation of gold nanoparticles confined at the water
surface are investigated by a suite of techniques, including grazing-incidence
x-ray photon correlation spectroscopy (GI-XPCS). The range of concentrations
studied spans across the percolation transition for the formation of the gel.
The dynamical features observed by GI-XPCS are interpreted in view of the
results of microscopical imaging; an intrinsic link between the mechanical
modulus and internal dynamics is demonstrated for all the concentrations. Our
work presents, to the best of our knowledge, the first example of a transition
from stretched to compressed correlation function actively controlled by
quasistatically varying the relevant thermodynamic variable. Moreover, by
applying a model proposed time ago by Duri and Cipelletti [A. Duri and L.
Cipelletti, Europhys. Lett. 76, 972 (2006)] we are able to build a novel master
curve for the shape parameter, whose scaling factor allows us to quantify a
'long time displacement length'. This characteristic length is shown to
converge, as the concentration is increased, to the 'short time localization
length' determined by pseudo Debye-Waller analysis of the initial contrast.
Finally, the intrinsic dynamics of the system are then compared with that
induced by means of a delicate mechanical perturbation applied to the
interface.


  Charge trapping and formation of polarons is a pervasive phenomenon in
transition metal oxide compounds, in particular at the surface, affecting
fundamental physical properties and functionalities of the hosting materials.
Here we investigate via first-principle techniques the formation and dynamics
of small polarons on the reduced surface of titanium dioxide, an archetypal
system for polarons, for a wide range of oxygen vacancy concentrations. We
report how the essential features of polarons can be adequately accounted in
terms of few quantities: the local structural and chemical environment, the
attractive interaction between negatively charged polarons and positively
charged oxygen vacancies, and the spin-dependent polaron-polaron Coulomb
repulsion. We combined molecular dynamics simulations on realistic samples
derived from experimental observations with simplified static models, aiming to
disentangle the various variables at play. We find that depending on the
specific trapping site, different types of polarons can be formed, with
distinct orbital symmetries and different degree of localization and structural
distortion. The energetically most stable polaron site is the subsurface Ti
atom below the undercoordinated surface Ti atom, owing to a small energy cost
to distort the lattice and a suitable electrostatic potential. Polaron-polaron
repulsion and polaron-vacancy attraction determine the spatial distribution of
polarons as well as the energy of the polaronic in-gap state. In the range of
experimentally reachable oxygen vacancy concentrations the calculated data are
in excellent agreement with observations, thus validating the overall
interpretation.


  We perform a numerical study of the evolution of a Coronal Mass Ejection
(CME) and its interaction with the coronal magnetic field based on the May 12,
1997, CME event using a global MagnetoHydroDynamic (MHD) model for the solar
corona. The ambient solar wind steady-state solution is driven by photospheric
magnetic field data, while the solar eruption is obtained by superimposing an
unstable flux rope onto the steady-state solution. During the initial stage of
CME expansion, the core flux rope reconnects with the neighboring field, which
facilitates lateral expansion of the CME footprint in the low corona. The flux
rope field also reconnects with the oppositely orientated overlying magnetic
field in the manner of the breakout model. During this stage of the eruption,
the simulated CME rotates counter-clockwise to achieve an orientation that is
in agreement with the interplanetary flux rope observed at 1 AU. A significant
component of the CME that expands into interplanetary space comprises one of
the side lobes created mainly as a result of reconnection with the overlying
field. Within 3 hours, reconnection effectively modifies the CME connectivity
from the initial condition where both footpoints are rooted in the active
region to a situation where one footpoint is displaced into the quiet Sun, at a
significant distance ($\approx 1R_\odot$) from the original source region. The
expansion and rotation due to interaction with the overlying magnetic field
stops when the CME reaches the outer edge of the helmet streamer belt, where
the field is organized on a global scale. The simulation thus offers a new view
of the role reconnection plays in rotating a CME flux rope and transporting its
footpoints while preserving its core structure.


  The evolution of the ground-state nuclear shapes in neutron-rich Sr, Zr, and
Mo isotopes, including both even-even and odd-A nuclei, is studied within a
self-consistent mean-field approximation based on the D1S Gogny interaction.
Neutron separation energies and charge radii are calculated and compared with
available data. A correlation between a shape transition and a discontinuity in
those observables is found microscopically. While in Sr and Zr isotopes the
steep behavior observed in the isotopic dependence of the charge radii is a
consequence of a sharp prolate-oblate transition, the smooth behavior found in
Mo isotopes has its origin in an emergent region of triaxiality.


  The highly transmissible COVID-19 disease is a serious threat to people's
health and life. To automate tracing those who have been in close physical
contact with newly infected people and/or to analyse tracing-related data,
researchers have proposed various ad-hoc programs that require being executed
on users' smartphones. Nevertheless, the existing solutions have two primary
limitations: (1) lack of generality: for each type of analytic task, a certain
kind of data needs to be sent to an analyst; (2) lack of transparency: parties
who provide data to an analyst are not necessarily infected individuals;
therefore, infected individuals' data can be shared with others (e.g., the
analyst) without their fine-grained and direct consent. In this work, we
present Glass-Vault, a protocol that addresses both limitations simultaneously.
It allows an analyst to run authorised programs over the collected data of
infectious users, without learning the input data. Glass-Vault relies on a new
variant of generic Functional Encryption that we propose in this work. This new
variant, called DD-Steel, offers these two additional properties: dynamic and
decentralised. We illustrate the security of both Glass-Vault and DD-Steel in
the Universal Composability setting. Glass-Vault is the first UC-secure
protocol that allows analysing the data of Exposure Notification users in a
privacy-preserving manner. As a sample application, we indicate how it can be
used to generate "infection heatmaps".


  We present a package to perform partial fraction decompositions of
multivariate rational functions. The algorithm allows to systematically avoid
spurious denominator factors and is capable of producing unique results also
when being applied to terms of a sum separately. The package is designed to
work in Mathematica, but also provides interfaces to the Form and Singular
computer algebra systems.


  We analyze the results by chiral NN models for the two-nucleon system and
calculate the predictions for the nucleon vector analyzing power of elastic
nucleon-deuteron (Nd) scattering, Ay, by these models. Our conclusion is that a
QUANTITATIVE chiral two-nucleon potential does not resolve the Nd Ay puzzle
(when only two-body forces are included).


  With the increasing prevalence of Machine Learning as a Service (MLaaS)
platforms, there is a growing focus on deep neural network (DNN) watermarking
techniques. These methods are used to facilitate the verification of ownership
for a target DNN model to protect intellectual property. One of the most widely
employed watermarking techniques involves embedding a trigger set into the
source model. Unfortunately, existing methodologies based on trigger sets are
still susceptible to functionality-stealing attacks, potentially enabling
adversaries to steal the functionality of the source model without a reliable
means of verifying ownership. In this paper, we first introduce a novel
perspective on trigger set-based watermarking methods from a feature learning
perspective. Specifically, we demonstrate that by selecting data exhibiting
multiple features, also referred to as \emph{multi-view data}, it becomes
feasible to effectively defend functionality stealing attacks. Based on this
perspective, we introduce a novel watermarking technique based on Multi-view
dATa, called MAT, for efficiently embedding watermarks within DNNs. This
approach involves constructing a trigger set with multi-view data and
incorporating a simple feature-based regularization method for training the
source model. We validate our method across various benchmarks and demonstrate
its efficacy in defending against model extraction attacks, surpassing relevant
baselines by a significant margin. The code is available at:
\href{https://github.com/liyuxuan-github/MAT}{https://github.com/liyuxuan-github/MAT}.


  We theoretically investigate the time dependence of the first order coherence
function for a one-dimensional driven dissipative non-equilibrium condensate.
Simulations on the generalized Gross-Pitaevskii equation (GGPE) show that the
characteristic time scale of exponential decay agrees with the linearized
Bogoliubov theory in the regime of large interaction energy. For very weak
interactions, the temporal correlation deviates from the linear theory, and
instead respects the dynamic scaling of the Kardar-Parisi-Zhang universality
class. This nonlinear dynamics is found to be quantitatively captured by a
noisy Kuramoto-Sivashinsky equation for the phase dynamics.


  In this paper, we establish a Schmidt's subspace theorem for moving
hyeprplane targets in projective spaces over function fields.


  The construction of type II Backlund transformation for the sine-Gordon and
the Tzitzeica-Bullough-Dodd models are obtained from gauge transformation. An
infinite number of conserved quantities are constructed from the defect
matrices. This guarantees that the introduction of type II defects for these
models does not spoil their integrability. In particular, modified energy and
momentum are derived and compared with those presented in recent literature.


  A new scheme of hard x-ray or gamma ray light is considered. The excitation
of the Langmuir wave in an ultra dense electron beamm via the two-stream
instabilities and the interaction of the excited Langmuir wave with the visible
light-laser results in hard x-ray or gamma ray via three-wave interaction. The
analysis suggests that the hard x-ray with the wave-lenght as small as 0.03 nm
can be achieved. The plausible parameter for the practical use is proposed and
the comparison with the conventional methods are provided.


  Distributed control increases system scalability, flexibility, and
redundancy. Foundational to such decentralisation is consensus formation, by
which decision-making and coordination are achieved. However, decentralised
multi-agent systems are inherently vulnerable to disruption. To develop a
resilient consensus approach, inspiration is taken from the study of social
systems and their dynamics; specifically, the Deffuant Model. A dynamic
algorithm is presented enabling efficient consensus to be reached with an
unknown number of disruptors present within a multi-agent system. By inverting
typical social tolerance, agents filter out extremist non-standard opinions
that would drive them away from consensus. This approach allows distributed
systems to deal with unknown disruptions, without knowledge of the network
topology or the numbers and behaviours of the disruptors. A disruptor-agnostic
algorithm is particularly suitable to real-world applications where this
information is typically unknown. Faster and tighter convergence can be
achieved across a range of scenarios with the social dynamics inspired
algorithm, compared with standard Mean-Subsequence-Reduced-type methods.


  Changes in brain states, as found in many neurological diseases such as
epilepsy, are often described as bifurcations in mesoscopic neural models.
Nearly all of these models rely on a mathematically convenient, but
biophysically inaccurate, description of the synaptic input to neurons called
current-based synapses. We develop a novel analytical framework to analyze the
effects of a more biophysically realistic description, known as
conductance-based synapses. These are implemented in a mesoscopic neural model
and compared to the standard approximation via a single parameter homotopic
mapping. A bifurcation analysis using the homotopy parameter demonstrates that
if a more realistic synaptic coupling mechanism is used in this class of
models, then a bifurcation or transition to an abnormal brain state does not
occur in the same parameter space. We show that the more realistic coupling has
additional mathematical parameters that require a fundamentally different
biophysical mechanism to undergo a state transition. These results demonstrate
the importance of incorporating more realistic synapses in mesoscopic neural
models and challenge the accuracy of previous models, especially those
describing brain state transitions such as epilepsy.


  Visual motion processing is essential for humans to perceive and interact
with dynamic environments. Despite extensive research in cognitive
neuroscience, image-computable models that can extract informative motion flow
from natural scenes in a manner consistent with human visual processing have
yet to be established. Meanwhile, recent advancements in computer vision (CV),
propelled by deep learning, have led to significant progress in optical flow
estimation, a task closely related to motion perception. Here we propose an
image-computable model of human motion perception by bridging the gap between
biological and CV models. Specifically, we introduce a novel two-stages
approach that combines trainable motion energy sensing with a recurrent
self-attention network for adaptive motion integration and segregation. This
model architecture aims to capture the computations in V1-MT, the core
structure for motion perception in the biological visual system, while
providing the ability to derive informative motion flow for a wide range of
stimuli, including complex natural scenes. In silico neurophysiology reveals
that our model's unit responses are similar to mammalian neural recordings
regarding motion pooling and speed tuning. The proposed model can also
replicate human responses to a range of stimuli examined in past psychophysical
studies. The experimental results on the Sintel benchmark demonstrate that our
model predicts human responses better than the ground truth, whereas the
state-of-the-art CV models show the opposite. Our study provides a
computational architecture consistent with human visual motion processing,
although the physiological correspondence may not be exact.


  This review paper is a continuation of hep-th/0012145 and it deals primarily
with noncommutative ${\mathbb R}^{d}$ spaces. We start with a discussion of
various algebras of smooth functions on noncommutative ${\mathbb R}^{d}$ that
have different asymptotic behavior at infinity. We pay particular attention to
the differences arising when working with nonunital algebras and the unitized
ones obtained by adjoining the unit element. After introducing main objects of
noncommutative geometry over those algebras such as inner products, modules,
connections, etc., we continue with a study of soliton and instanton solutions
in field theories defined on these spaces. The discussion of solitons includes
the basic facts regarding the exact soliton solutions in the Yang-Mills-Higgs
systems as well as an elementary discussion of approximate solitons in scalar
theories in the $\theta \to \infty$ limit. We concentrate on the module
structure and topological numbers characterizing the solitons. The section on
instantons contains a thorough description of noncommutative ADHM construction,
a discussion of gauge triviality conditions at infinity and the structure of a
module underlying the ADHM instanton solution. Although some familiarity with
general ideas of noncommutative geometry reviewed in the first part is expected
from the reader, this part is largely independent from the first one.


  We extend Wegner's exact solution for the 2D density of states at the lowest
Landau level with a short--range disorder to the cases of a double--layer
system and a superlattice. For the double--layer system, an analytical
expression for the density of states, illustrating the interplay between the
tunnel splitting of Landau levels and the disorder--induced broadening, is
obtained. For the superlattice, we derive an integral equation, the eigenvalue
of which determines the exact density of states. By solving this equation
numerically, we trace the disappearance of the miniband with increasing
disorder.


  Moir\'e potential acts as periodic quantum confinement for optically
generated exciton, generating spatially ordered zero-dimensional quantum
system. However, broad emission spectrum arising from inhomogeneity among
moir\'e potential hinders the exploration of the intrinsic properties of
moir\'e exciton. In this study, we have demonstrated a new method to realize
the optical observation of quantum coherence and interference of a single
moir\'e exciton in twisted semiconducting heterobilayer beyond the diffraction
limit of light. A significant single and sharp photoluminescence peak from a
single moir\'e exciton has been demonstrated after nano-fabrication. We present
the longer duration of quantum coherence of a single moir\'e exciton, which
reaches beyond 10 ps and the accelerated decoherence process with elevating
temperature and excitation power density. Moreover, the quantum interference
has revealed the coupling between moir\'e excitons in different moir\'e
potential minima. The observed quantum coherence and interference of moir\'e
exciton will facilitate potential application toward quantum technologies based
on moir\'e quantum systems.


  We report the first measurement of the isotope fraction of europium (151Eu
and 153Eu) for the extremely metal-poor, r-process-enhanced star CS31082-001,
based on high-resolution spectra obtained with the Subaru Telescope High
Dispersion Spectrograph. We have also obtained new measurements of this ratio
for two similar stars with previous europium isotope measurements, CS22892-052
and HD115444. The measurements were made using observations of the Eu lines in
these spectra that are most significantly affected by isotope shifts and
hyperfine splitting. The fractions of 151Eu derived for CS31082-001,
CS22892-052, and HD115444 are 0.44, 0.51, and 0.46, respectively, with
uncertainties of about +/-0.1. CS31082-001, the first star with a meaningful
measurement of U outside of the solar system, is known to exhibit peculiar
abundance ratios between the actinide and rare-earth elements (e.g., Th/Eu),
ratios that are significantly different from those for other stars with large
excesses of r-process elements, such as our two comparison objects.
Nevertheless, our analysis indicates that the Eu isotope ratio of CS31082-001
agrees, within the errors, with those of other r-process-enhanced objects, and
with that of solar-system material.


  A framework for studying knot and link invariants from any rational conformal
field theory is developed. In particular, minimal models, superconformal models
and $W_N$ models are studied. The invariants are related to the invariants
obtained from the Wess-Zumino models associated with the coset representations
of these models. Possible Chern-Simons representation of these models is also
indicated. This generalises the earlier work on knot and link invariants from
Chern-Simons theories.


  Let K be an algebraically closed field. We prove that a polynomial
K-derivation $D$ in two variables is locally nilpotent if and only if the
subgroup of polynomial K-automorphisms which commute with D admits elements
whose degree is arbitrary big.


  In this paper, Neumann cracks in elastic bodies are considered. We establish
a rigorous asymptotic expansion for the boundary perturbations of the
displacement (and traction) vectors that are due to the presence of a small
elastic linear crack. The formula reveals that the leading order term is
\epsilon^2 where \epsilon is the length of the crack, and the \epsilon^3-term
vanishes. We obtain an asymptotic expansion of the elastic potential energy as
an immediate consequence of the boundary perturbation formula. The derivation
is based on layer potential techniques. It is expected that the formula would
lead to very effective direct approaches for locating a collection of small
elastic cracks and estimating their sizes and orientations.


  In cloud computing environments, a large number of users access data stored
in highly available storage systems. To provide good performance to
geographically disperse users and allow operation even in the presence of
failures or network partitions, these systems often rely on optimistic
replication solutions that guarantee only eventual consistency. In this
scenario, it is important to be able to accurately and efficiently identify
updates executed concurrently. In this paper, first we review, and expose
problems with current approaches to causality tracking in optimistic
replication: these either lose information about causality or do not scale, as
they require replicas to maintain information that grows linearly with the
number of clients or updates. Then, we propose a novel solution that fully
captures causality while being very concise in that it maintains information
that grows linearly only with the number of servers that register updates for a
given data element, bounded by the degree of replication.


  A sequence of two and three-dimensional simulations is conducted for the
double diffusive convection (DDC) flows in the diffusive regime subjected to an
imposed shear. The flow is confined between two horizontal plates which are
maintained at different constant temperature, salinity, and different velocity,
thus setting up a shear across the flow. The lower plate is fixed at higher
temperature and salinity, while the overall (unperturbed) density gradient is
statically stable. For a wide range of control parameters, and for sufficiently
strong perturbation of the conductive initial state, we find that
staircase-like structures spontaneously develop, with relatively well-mixed
layers separated by sharp interfaces of enhanced scalar gradient. Such
staircases appear to be robust even in the presence of strong shear over very
long times, although we typically observe early time coarsening of the number
of observed layers. For the same set of control parameters, different
asymptotic layered states, with markedly different vertical scalar fluxes, can
arise for different initial perturbation structures. The imposed shear does
significantly spatio-temporally modify the vertical transport of the various
scalars. The flux ratio (i.e., the ratio between the density fluxes due to the
total (convective and diffusive) salt flux and the total heat flux) is found,
at steady state, to be essentially equal to the square root of the ratio of the
salt diffusivity to the thermal diffusivity, consistently with the physical
model originally proposed by Linden and Shirtcliffe (1978) and the variational
arguments presented by Stern (1982) for unsheared double diffusive convection.


  Macroscale chains have been proposed to give insight into the physics of
molecular polymer systems. Nevertheless, understanding the rheological response
of systems of quasi-one-dimensional semiflexible materials, such as bead-chain
packings, is currently a great challenge. We study the nonlinear rheology of
random assemblies of macroscale chains -- including steel bead chains and
cooked spaghetti -- under oscillatory shear. We show that a universal
transition from localized to wide shear zones occurs upon increasing the strain
amplitude, for a wide range of lengths, flexibilities, and other structural
parameters of the constituent elements. The critical strain amplitude coincides
with the onset of strain stiffening development in the system. We obtain
scaling laws for transition sharpness, shear-zone width, and stiffness
enhancement as a function of chain length. Our findings suggest that the
entanglements between the constituent elements strengthen when approaching the
critical strain amplitude and rapidly become long range, even spanning the
entire finite system for long enough chains. We show that the nonlinear
rheological response is governed by the interplay between increasing stored
elastic forces due to entanglements and increasing contribution of dissipation
with shear rate and interlocking between chains.


  We describe the cryogenic half-wave plate rotation mechanisms built for and
used in Spider, a polarization-sensitive balloon-borne telescope array that
observed the Cosmic Microwave Background at 95 GHz and 150 GHz during a
stratospheric balloon flight from Antarctica in January 2015. The mechanisms
operate at liquid helium temperature in flight. A three-point contact design
keeps the mechanical bearings relatively small but allows for a large (305 mm)
diameter clear aperture. A worm gear driven by a cryogenic stepper motor allows
for precise positioning and prevents undesired rotation when the motors are
depowered. A custom-built optical encoder system monitors the bearing angle to
an absolute accuracy of +/- 0.1 degrees. The system performed well in Spider
during its successful 16 day flight.


  The detection of planets around very low-mass stars with the radial velocity
method is hampered by the fact that these stars are very faint at optical
wavelengths where the most high-precision spectrometers operate. We investigate
the precision that can be achieved in radial velocity measurements of low mass
stars in the near infrared (nIR) Y-, J-, and H-bands, and we compare it to the
precision achievable in the optical. For early-M stars, radial velocity
measurements in the nIR offer no or only marginal advantage in comparison to
optical measurements. Although they emit more flux in the nIR, the richness of
spectral features in the optical outweighs the flux difference. We find that
nIR measurement can be as precise than optical measurements in stars of
spectral type ~M4, and from there the nIR gains in precision towards cooler
objects. We studied potential calibration strategies in the nIR finding that a
stable spectrograph with a ThAr calibration can offer enough wavelength
stability for m/s precision. Furthermore, we simulate the wavelength-dependent
influence of activity (cool spots) on radial velocity measurements from optical
to nIR wavelengths. Our spot simulations reveal that the radial velocity jitter
does not decrease as dramatically towards longer wavelengths as often thought.
The jitter strongly depends on the details of the spots, i.e., on spot
temperature and the spectral appearance of the spot. Forthcoming nIR
spectrographs will allow the search for planets with a particular advantage in
mid- and late-M stars. Activity will remain an issue, but simultaneous
observations at optical and nIR wavelengths can provide strong constraints on
spot properties in active stars.


  We solve difficult word-based substitution codes by constructing a decoding
lattice and searching that lattice with a neural language model. We apply our
method to a set of enciphered letters exchanged between US Army General James
Wilkinson and agents of the Spanish Crown in the late 1700s and early 1800s,
obtained from the US Library of Congress. We are able to decipher 75.1% of the
cipher-word tokens correctly.


  Localization of low-cost Unmanned Aerial Vehicles (UAVs) often relies on
Global Navigation Satellite Systems (GNSS). GNSS are susceptible to both
natural disruptions to radio signal and intentional jamming and spoofing by an
adversary. A typical way to provide georeferenced localization without GNSS for
small UAVs is to have a downward-facing camera and match camera images to a
map. The downward-facing camera adds cost, size, and weight to the UAV platform
and the orientation limits its usability for other purposes. In this work, we
propose a Monte-Carlo localization method for georeferenced localization of an
UAV requiring no infrastructure using only inertial measurements, a camera
facing an arbitrary direction, and an orthoimage map. We perform
orthorectification of the UAV image, relying on a local planarity assumption of
the environment, relaxing the requirement of downward-pointing camera. We
propose a measure of goodness for the matching score of an orthorectified UAV
image and a map. We demonstrate that the system is able to localize globally an
UAV with modest requirements for initialization and map resolution.