  Noncommutative algebra in planar quantum mechanics is shown to follow from 't
Hooft's recent analysis on dissipation and quantization. The noncommutativity
in the coordinates or in the momenta of a charged particle in a magnetic field
with an oscillator potential are shown as dual descriptions of the same
phenomenon. Finally, noncommutativity in a fluid dynamical model, analogous to
the lowest Landau level problem, is discussed.


  Several theoretical works have shown that solitons -- waves that
self-maintain constant shape and velocity as they propagate -- can be used as a
physical computational reservoir, a concept where machine learning algorithms
designed for digital computers are replaced by analog physical systems that
exhibit nonlinear dynamical behaviour. Here we propose and experimentally
validate a novel reservoir computing (RC) system that for the first time
employs solitary-like (SL) waves propagating on the surface of a liquid film
flowing over an inclined surface. We demonstrate the ability of the SL wave RC
system (SLRC) to forecast chaotic time series and to successfully pass
essential benchmark tests, including a memory capacity test and a Mackey-Glass
model test.


  In this paper we consider a system of parabolic reaction-diffusion equations
with strong competition and two related scalar reaction-diffusion equations. We
are mainly concerned with the case of periodic coefficients and periodic
solutions. We show that, for sufficiently large periods, these models have
stationary, non-constant, fully non-trivial and stable solutions. We compare
our results with already known results about the existence and non-existence of
such solutions. Finally, we provide ecological interpretations for these
results in terms of resistance against an invasion.


  Physical modeling method, represented by simulation and visualization of the
principles in physics, is introduced in the shape extraction of the active
contours. The objectives of adopting this concept are to address the several
major difficulties in the application of Active Contours. Primarily, a
technique is developed to realize the topological changes of Parametric Active
Contours (Snakes). The key strategy is to imitate the process of a balloon
expanding and filling in a closed space with several objects. After removing
the touched balloon surfaces, the objects can be identified by surrounded
remaining balloon surfaces. A burned region swept by Snakes is utilized to
trace the contour and to give a criterion for stopping the movement of Snake
curve. When the Snakes terminates evolution totally, through ignoring this
criterion, it can form a connected area by evolving the Snakes again and
continuing the region burning. The contours extracted from the boundaries of
the burned area can represent the child snake of each object respectively.
Secondly, a novel scheme is designed to solve the problems of leakage of the
contour from the large gaps, and the segmentation error in Geometric Active
Contours (GAC). It divides the segmentation procedure into two processing
stages. By simulating the wave propagating in the isotropic substance at the
final stage, it can significantly enhance the effect of image force in GAC
based on Level Set and give the satisfied solutions to the two problems.
Thirdly, to support the physical models for active contours above, we introduce
a general image force field created on a template plane over the image plane.
This force is more adaptable to noisy images with complicated geometric shapes.


  We study the low-temperature thermal conductivity (\kappa) of Dy_2Ti_2O_7
along and perpendicular to the (111) plane and under the magnetic field along
the [111] direction. Besides the step-like decreases of \kappa at the
field-induced transitions from the spin-ice state to the kagom\'e-ice state and
then to the polarized state, an abnormal phenomenon is that the \kappa(H)
isotherms show a clear irreversibility at very low temperatures upon sweeping
magnetic field up and down. This phenomenon surprisingly has no correspondence
with the well-known magnetization hysteresis. Possible origins for this
irreversibility are discussed; in particular, a pinning effect of magnetic
monopoles in spin ice compound by the weak disorders is proposed.


  In this paper, superimposed pilots are introduced as an alternative to
time-multiplexed pilot and data symbols for mitigating pilot contamination in
massive multiple-input multiple-output (MIMO) systems. We propose a
non-iterative scheme for uplink channel estimation based on superimposed pilots
and derive an expression for the uplink signal-to-interference-plus-noise ratio
(SINR) at the output of a matched filter employing this channel estimate. Based
on this expression, we observe that power control is essential when
superimposed pilots are employed. Moreover, the quality of the channel estimate
can be improved by reducing the interference that results from transmitting
data alongside the pilots, and an intuitive iterative data-aided scheme that
reduces this component of interference is also proposed. Approximate
expressions for the uplink SINR are provided for the iterative data-aided
method as well. In addition, we show that a hybrid system with users utilizing
both time-multiplexed and superimposed pilots is superior to an optimally
designed system that employs only time-multiplexed pilots, even when the
non-iterative channel estimate is used to build the detector and precoder. We
also describe a simple approach to implement this hybrid system by minimizing
the overall inter and intra-cell interference. Numerical simulations
demonstrating the performance of the proposed channel estimation schemes and
the superiority of the hybrid system are also provided.


  We study the effects of the presence of contrarians in an agent-based model
of competing populations. Contrarians are common in societies. These
contrarians are agents who deliberately prefer to hold an opinion that is
contrary to the prevailing idea of the commons or normal agents. Contrarians
are introduced within the context of the Minority Game (MG), which is a binary
model for an evolving and adaptive population of agents competing for a limited
resource. Results of numerical simulations reveal that the average success rate
among the agents depends non-monotonically on the fraction $a_{c}$ of
contrarians. For small $a_{c}$, the contrarians systematically outperform the
normal agents by avoiding the crowd effect and enhance the overall success
rate. For high $a_{c}$, the anti-persistent nature of the MG is disturbed and
the few normal agents outperform the contrarians. Qualitative discussion and
analytic results for the small $a_{c}$ and high $a_{c}$ regimes are also
presented, and the crossover behavior between the two regimes is discussed.


  We investigate the Full Counting Statistics of an electrical Mach-Zehnder
interferometer penetrated by an Aharonov-Bohm flux, and in the presence of a
classical fluctuating potential. Of interest is the suppression of the
Aharonov-Bohm oscillations in the distribution function of the transmitted
charge. For a Gaussian fluctuating field we calculate the first three
cumulants. The fluctuating potential causes a modulation of the conductance
leading in the third cumulant to a term cubic in voltage and to a contribution
correlating modulation of current and noise. In the high voltage regime we
present an approximation of the generating function.


  The saltatory propagation of action potentials on myelinated axons is
conventionally explained by the mechanism employing local circuit ionic current
flows between nodes of Ranvier. Under this framework, the myelin sheath with up
to 100 layers of membrane only serves as the insulating shell. The speed of
action potentials is measured to be as fast as 100 m/s on myelinated axons, but
ions move in fluids at just 100 nm/s in a 1 V/m electric field. We show here
the action potentials, in the form of electromagnetic (EM) pulses, can
propagate in natural EM waveguide structures formed by the myelin sheath merged
in fluids. The propagation time is mainly cost on the duration for triggering
EM pulses at nodes of Ranvier. The result clearly reveals the evolution of
axons from the unmyelinated to the myelinated, which has remarkably enhanced
the propagation efficiency by increasing the thickness of myelin sheath.


  An analysis of MHD wave propagating in a gravitating and rotating medium
permeated by non-uniform magnetic field has been done. It has been found that
the Gradient of Magnetic Field when coupled with Rotation becomes capable to
generate few instabilities (Temporal or Spatial) leading to the damping or
amplification of MHD waves. The Jean's criterion is not sufficient for
stability always. Rather, the waves will suffer instability unless their wave
length (frequency) is less (greater) than certain critical values. Otherwise,
those will smoothly propagate outward. Out of different scenarioes depending on
the direction of the magnetic field, its gradient, rotation and wave
propagation three important Special Cases have been discussed and different
stability criteria have been derived.
  Finally, using the above theory we have obtained the stability/instability
criteria for the waves moving parallel and perpendicular to the galactic plane
in the Core and Periphery of the Central Region of Galaxy (C.R.G.) due to the
coupled action of Rotation and Non-Uniform Magnetic field. The possibility of
heating or occuring diffused condition inside the central region by MHD waves
or smooth propagation of these waves (under some restrictions) through the
C.R.G. has been briefly discussed. The numerical values of the parameters of
those waves for instabilities or smooth propagation have been estimated
roughly. One may find some clues for the formation of Halo and Spiral Arms.


  The coupled Einstein-Dirac-Maxwell equations are considered for a static,
spherically symmetric system of two fermions in a singlet spinor state. Stable
soliton-like solutions are shown to exist, and we discuss the regularizing
effect of gravity from a Feynman diagram point of view.


  We demonstrate singlet-triplet readout and parity readout allowing to
distinguish T0 and the polarized triplet states. We achieve high fidelity spin
readout with an average fidelity above $99.9\%$ for a readout time of $20~\mu$s
and $99\%$ for $4~\mu$s at a temperature of $0.5~K$. We initialize a singlet
state in a single dot with a fidelity higher than $99\%$ and separate the two
electrons while keeping the same spin state with $a \approx 95.6\%$ fidelity.


  The purpose of this review it to present a renewed perspective of the problem
of self-gravitating elastic bodies under spherical symmetry. It is also a
companion to the papers [Phys. Rev. D105, 044025 (2022)], [Phys. Rev. D106,
L041502 (2022)], and [arXiv:2306.16584 [gr-qc]], where we introduced a new
definition of spherically symmetric elastic bodies in general relativity, and
applied it to investigate the existence and physical viability, including
radial stability, of static self-gravitating elastic balls. We focus on elastic
materials that generalize fluids with polytropic, linear, and affine equations
of state, and discuss the symmetries of the energy density function, including
homogeneity and the resulting scale invariance of the TOV equations. By
introducing invariant characterizations of physical admissible initial data, we
numerically construct mass-radius-compactness diagrams, and conjecture about
the maximum compactness of stable physically admissible elastic balls.


  The Leggett-Garg inequality (LGI), based on the notions of realism and
noninvasive measurability, is applied in the context of a linear harmonic
oscillator. It is found that merely through observing at various instants which
region of the potential well, the oscillating quantum object is in, the LGI can
be violated without taking recourse to any ancillary quantum system.
Strikingly, this violation reveals an unexplored nonclassicality of the state
which is considered the most "classical-like" of all quantum states, namely the
Schr\"odinger coherent state. In the macrolimit, the extent to which such
nonclassicality persists for large values of mass and classical amplitudes of
oscillation is quantitatively investigated. It is found that while for any
given mass and oscillator frequency, a significant quantum violation of LGI can
be obtained by suitably choosing the initial peak momentum of the coherent
state wave packet, as the mass is sufficiently increased, actual observability
of this violation becomes increasingly difficult. A feasible experimental setup
for testing the predicted quantum mechanical violation of LGI is suggested
using a trapped nano-object of $\sim 10^6-10^9$ amu mass.


  We develop the analog of crystalline Dieudonn\'e theory for p-divisible
groups in the arithmetic of function fields. In our theory p-divisible groups
are replaced by divisible local Anderson modules, and Dieudonn\'e modules are
replaced by local shtukas. We show that the categories of divisible local
Anderson modules and of effective local shtukas are anti-equivalent over
arbitrary base schemes. We also clarify their relation with formal Lie groups
and with global objects like Drinfeld modules, Anderson's abelian t-modules and
t-motives, and Drinfeld shtukas. Moreover, we discuss the existence of a
Verschiebung map and apply it to deformations of local shtukas and divisible
local Anderson modules. As a tool we use Faltings's and Abrashkin's theory of
strict modules, which we review to some extent.


  The SPIRE Photometer Simulator reproduces the entire Herschel-SPIRE system in
a modular IDL program. Almost every aspect of the operation of SPIRE can be
investigated in a systematic way to ensure that observations are performed in
the most efficient way possible when Herschel flies. This paper describes some
of the work done with the Simulator to help prepare for large observing
programmes such as deep extra-galactic, high-redshift surveys.


  Eye-strain is a common issue among computer users due to the prolonged
periods they spend working in front of digital displays. This can lead to
vision problems, such as irritation and tiredness of the eyes and headaches. We
propose the Eye-Strain Probation Model (ESPiM), a computational model based on
eye-tracking data that measures eye-strain on digital displays based on the
spatial properties of the user interface and display area for a required period
of time. As well as measuring eye-strain, ESPiM can be applied to compare (a)
different user interface designs, (b) different display devices, and (c)
different interaction techniques. Two user studies were conducted to evaluate
the effectiveness of ESPiM. The first was conducted in the form of an in-person
study with an infrared eye-tracking sensor with 32 participants. The second was
conducted in the form of an online study with a video-based eye-tracking
technique via webcams on users' computers with 13 participants. Our analysis
showed significantly different eye-strain patterns based on the video gameplay
frequency of participants. Further, we found distinctive patterns among users
on a regular 9-to-5 routine versus those with more flexible work hours in terms
of (a) error rates and (b) reported eye-strain symptoms.


  Inspired by the works of Y. Ohta and J. Yang, one constructs the lumps
solutions in the Kadomtsev-Petviashvili-(I) equation using the Grammian
determinants. It is shown that the locations of peaks will depend on the real
roots of Wronskian of the orthogonal polynomials for the asymptotic behaviors
in some particular cases. Also, one can prove that all the locations of peaks
are on a vertical line when time approaches - $\infty$, and then they will be
on a horizontal line when time approaches $\infty$, i.e., there is a rotation
$\frac{\pi}{2}$ after interaction.


  We consider string theory on AdS$_3$ $\times$ (S$^3$ $\times$ S$^3$ $\times$
S$^1)/\mathbb Z_2$, a background supporting $\mathcal N=(3,3)$ spacetime
supersymmetry. We propose that string theory on this background is dual to the
symmetric product orbifold of $\mathcal S_0/\mathbb Z_2$ where $\mathcal S_0$
is a theory of four free fermions and one free boson. We show that the BPS
spectra of the two sides of the duality match precisely. Furthermore, we
compute the elliptic genus of the dual CFT and that of the supergravity limit
of string theory and demonstrate that they match, hence providing non-trivial
support for the holographic proposal.


  Recently, both charge density wave (CDW) and superconductivity have been
observed in Kagome compounds $A$V$_3$Sb$_5$. However, the nature of CDW that
results in many novel charge modulations is still under hot debate.
  By means of the first-principles calculations, we discover two kinds of CDW
states, the trimerized and hexamerized 2$\times$2 phase and dimerized
4$\times$1 phase existing in $A$V$_3$Sb$_5$.
  Our phonon excitation spectrum and electronic Lindhard function calculations
reveal that the most intensive structural instability in $A$V$_3$Sb$_5$
originates from a combined in-plane vibration mode of V atoms through the
electron-phonon coupling, rather than the Fermi surface nesting effect.
  Crucially, a metastable 4$\times$1 phase with V-V dimer pattern and twofold
symmetric bowtie shaped charge modulation is revealed in CsV$_3$Sb$_5$,
implying that both dimerization and trimerization exist in the V Kagome layers.
  These results provide essential understanding of CDW instability and new
thoughts for the novel charge modulation patterns.


  With nucleons occupying an oscillator shell $\eta$, there are $2^{\eta/2}$
number of $SU(3)$ algebras; $\eta/2$ is the integer part of $\eta/2$. Analyzing
the first non trivial situation with four $SU(3)$ algebras in $(sdg)$ space,
demonstrated recently is that they generate quite different quadrupole
properties though they all generate the same spectrum. More complex situation
is with eight $SU(3)$ algebras in $(sdgi)$ space. In the present work,
quadrupole properties generated by these eight algebras are analyzed first
using the more analytically tractable interacting boson model. In addition,
shell model and the closely related deformed shell model are used with three
examples of nucleons in $sdgi$ space. It is found that in general six of the
$SU(3)$ algebras generate prolate shape and two oblate shape. Out of all these,
one of the $SU(3)$ algebra generates quite small quadrupole moments for the
low-lying states.


  We study the problem of consistent query answering under primary key
violations. In this setting, the relations in a database violate the key
constraints and we are interested in maximal subsets of the database that
satisfy the constraints, which we call repairs. For a boolean query Q, the
problem CERTAINTY(Q) asks whether every such repair satisfies the query or not;
the problem is known to be always in coNP for conjunctive queries. However,
there are queries for which it can be solved in polynomial time. It has been
conjectured that there exists a dichotomy on the complexity of CERTAINTY(Q) for
conjunctive queries: it is either in PTIME or coNP-complete. In this paper, we
prove that the conjecture is indeed true for the case of conjunctive queries
without self-joins, where each atom has as a key either a single attribute
(simple key) or all attributes of the atom.


  In one and two component solvents, we calculate the counterion distribution
around a charged rod treating the degree of ionization $\alpha$ as an annealed
variable dependent on its local environment. In the one component case,
$\alpha$ is determined under various conditions without and with salt. In the
two component case, we take into account the preferential solvation of the
counterions and the ionized monomers and the short-range interaction between
the rod and the solvent without salt. It then follows a composition-dependent
mass action law. Mesoscopic variations of the composition and the counterions
are produced around a chraged rod, which sensitively depend on various
parameters of the molecular interactions.
  Furthermore, we predict a first order phase transition of weak-to-strong
dissociation for strong preferential solvation. It can occur in expanded states
of a polymer chain. This transition line starts from a point on the solvent
coexistence curve and ends at a critical point in the plane of the temperature
and the solvent composition. The composition change around a charged rod is
long-ranged near the solvent critical point.


  We present the results of the most comprehensive survey of the Galactic plane
in very high-energy (VHE) gamma-rays, including a public release of Galactic
sky maps, a catalog of VHE sources, and the discovery of 16 new sources of VHE
gamma-rays. The High Energy Spectroscopic System (H.E.S.S.) Galactic plane
survey (HGPS) was a decade-long observation program carried out by the H.E.S.S.
I array of Cherenkov telescopes in Namibia from 2004 to 2013. The observations
amount to nearly 2700 h of data, covering the Galactic plane at longitudes from
l = 250 deg to 65 deg and latitudes |b| < 3 deg. In addition to the
unprecedented spatial coverage, the HGPS also features a relatively high
angular resolution (0.08 deg), sensitivity (1.5% Crab flux for point-like
sources), and energy range (0.2-100 TeV). We constructed a source catalog with
a systematic procedure for both source detection and characterization of
morphology and spectrum. We present this method, including the introduction of
a model component to account for unresolved, large-scale emission along the
Galactic plane. In total, the resulting HGPS catalog contains 78 VHE sources,
of which 14 are not reanalyzed here. Where possible, we provide a firm
identification of the VHE source or plausible associations with sources in
other astronomical catalogs. We also studied the characteristics of the VHE
sources with source parameter distributions. 16 new sources were previously
unknown or unpublished, and we individually discuss their identifications or
possible associations. We firmly identified 31 sources as pulsar wind nebulae
(PWNe), supernova remnants (SNRs), composite SNRs, or gamma-ray binaries. Among
the 47 sources not yet identified, most of them (36) have possible associations
with cataloged objects, notably PWNe and energetic pulsars that could power VHE
PWNe.


  Objects that are on the threshold of forming the horizon but never collapse
are called quasi-black holes (QBHs). We discuss the properties of the general
spherically symmetric QBH metric without addressing its material source,
including its limiting cases as the corresponding small parameter tends to
zero. We then show that QBHs can exist among self-gravitating configurations of
electromagnetic and dilatonic scalar fields without matter. These general
results are illustrated by explicit examples of exact solutions.


  General solutions for braneworld dynamics coupled with the bulk Einstein
equation are derived under the Schwarzschild ansatz. They relate the brane
metric to the exterior configurations, and establish fine tuning conditions for
the braneworlds to reproduce successes of the Einstein gravity.


  Examples of one-dimensional lattice systems are considered, in which patterns
of different spatial scales arise alternately, so that the spatial phase over a
full cycle undergo transformation according to expanding circle map that
implies occurrence of Smale-Williams attractors in the multidimensional state
space. These models can serve as a basis for design electronic generators of
robust chaos within a paradigm of coupled cellular networks. One of the
examples is a mechanical pendulum system interesting and demonstrative for
research and educational experimental studies.


  In \cite{QR19}, Qing, Rafi and Tiozzo introduced the sublinearly contracting
boundary for CAT(0) spaces. Every point of this boundary is uniquely
represented by a sublinearly contracting geodesic ray: a geodesic ray $b$ where
every disjoint ball projects to a subset whose diameter is bounded by a
sublinear function in terms of the ball's distance to the origin. This paper
analyzes the bahaviour of horofunctions associated to such geodesic rays, for
example, we show that horospheres associated to such horofunctions are
convergent. As a consequence of this analysis, we show that for any proper
complete CAT(0) space $X$, every point of the visual boundary $\partial X$ that
is defined by a sublinearly contracting geodesic ray is a visibility point.


  We apply the K-correction to the black hole LMXB GX 339-4 which implies Mx >
6 Msun by only assuming that the companion is more massive than ~0.17 Msun, the
lower limit allowed by applying a 'stripped-giant' model. This evolutionary
model successfully reproduces the observed properties of the system. We obtain
a maximum mass for the companion of M2 < 1.1 Msun and an upper limit to the
mass ratio of q(=M2/Mx)< 0.125. The high X-ray activity displayed by the source
suggests a relatively large mass transfer rate which, according to the model,
results in M2 > 0.3 Msun and Mx > 7 Msun. We have also applied this scenario to
the black hole binary XTE J1550-564, which has a similar orbital period but the
donor is detected spectroscopically. The model successfully reproduces the
observed stellar parameters.


  This paper is devoted to the development and convergence analysis of greedy
reconstruction algorithms based on the strategy presented in [Y. Maday and J.
Salomon, Joint Proceedings of the 48th IEEE Conference on Decision and Control
and the 28th Chinese Control Conference, 2009, pp. 375--379]. These procedures
allow the design of a sequence of control functions that ease the
identification of unknown operators in nonlinear dynamical systems. The
original strategy of greedy reconstruction algorithms is based on an
offline/online decomposition of the reconstruction process and an ansatz for
the unknown operator obtained by an a priori chosen set of linearly independent
matrices. In the previous work [S. Buchwald, G. Ciaramella and J. Salomon, SIAM
J. Control Optim., 59(6), pp. 4511-4537], convergence results were obtained in
the case of linear identification problems. We tackle here the more general
case of nonlinear systems. More precisely, we introduce a new greedy algorithm
based on the linearized system. Then, we show that the controls obtained with
this new algorithm lead to the local convergence of the classical Gauss-Newton
method applied to the online nonlinear identification problem. We then extend
this result to the controls obtained on nonlinear systems where a local
convergence result is also proved. The main convergence results are obtained
for the reconstruction of drift operators in dynamical systems with linear and
bilinear control structures.


  Adsorption of para-Hydrogen on the surface of graphite pre-plated with a
single layer of atomic krypton is studied thoretically by means of Path
Integral Ground State Monte Carlo simulations. We compute energetics and
density profiles of para-hydrogen, and determine the structure of the adsorbed
film for various coverages. Results show that there are two thermodynamically
stable monolayer phases of para-hydrogen, both solid. One is commensurate with
the krypton layer, the other is incommensurate. No evidence is seen of a
thermodynamically stable liquid phase, at zero temperature. These results are
qualitatively similar to what is seen for for para-hydrogen on bare graphite.
Quantum exchanges of hydrogen molecules are suppressed in this system.


  A two-component Bose-Einstein condensate of cold atoms with a strong
intercomponent repulsion leading to the spatial separation of the components
has been numerically studied. Configurations with a multiple quantized vortex
in one component, where the vortex core is filled with the other component, are
considered. The effective radius of the core can exceed the width of the
transition layer between components, and then an analogy with a filled
cylindrical vortex in the classical hydrodynamics of two immiscible ideal
fluids appears. This analogy allows one to analyze the longitudinal "sausage"
instability and the transverse instability of the filled vortex in the
condensate caused by the "tangential discontinuity," as well as the stable
regime in the parametric gap between them. The presence of long-lived coherent
structures formed in some cases at the nonlinear stages of both instabilities
is numerically discovered.


  We discuss the compact support property of the rough super-Brownian motion
constructed as a scaling limit of a branching random walk in static random
environment. The semi-linear equation corresponding to this measure-valued
process is the continuous parabolic Anderson model, a singular SPDE in need of
renormalization, which prevents the use of classical PDE arguments. But with
the help of an interior estimation method, we are able to show that the compact
support property also holds for rough super-Brownian motion.


  Preservation of the maximum principle is studied for the combination of the
linear finite element method in space and the $\theta$-method in time for
solving time dependent anisotropic diffusion problems. It is shown that the
numerical solution satisfies a discrete maximum principle when all element
angles of the mesh measured in the metric specified by the inverse of the
diffusion matrix are non-obtuse and the time step size is bounded below and
above by bounds proportional essentially to the square of the maximal element
diameter. The lower bound requirement can be removed when a lumped mass matrix
is used. In two dimensions, the mesh and time step conditions can be replaced
by weaker Delaunay-type conditions. Numerical results are presented to verify
the theoretical findings.


  We study finite-frequency transport properties of the double-dot system
recently constructed to observe the two-channel Kondo effect [R. M. Potok et
al., Nature 446, 167 (2007)]. We derive an analytical expression for the
frequency-dependent linear conductance of this device in the Kondo regime. We
show how the features characteristic of the 2-channel Kondo quantum critical
point emerge in this quantity, which we compute using the results of conformal
field theory as well as numerical renormalization group methods. We determine
the universal cross-over functions describing non-Fermi liquid vs. Fermi liquid
cross-overs and also investigate the effects of a finite magnetic field.


  The White House Executive Order on Artificial Intelligence highlights the
risks of large language models (LLMs) empowering malicious actors in developing
biological, cyber, and chemical weapons. To measure these risks of malicious
use, government institutions and major AI labs are developing evaluations for
hazardous capabilities in LLMs. However, current evaluations are private,
preventing further research into mitigating risk. Furthermore, they focus on
only a few, highly specific pathways for malicious use. To fill these gaps, we
publicly release the Weapons of Mass Destruction Proxy (WMDP) benchmark, a
dataset of 3,668 multiple-choice questions that serve as a proxy measurement of
hazardous knowledge in biosecurity, cybersecurity, and chemical security. WMDP
was developed by a consortium of academics and technical consultants, and was
stringently filtered to eliminate sensitive information prior to public
release. WMDP serves two roles: first, as an evaluation for hazardous knowledge
in LLMs, and second, as a benchmark for unlearning methods to remove such
hazardous knowledge. To guide progress on unlearning, we develop RMU, a
state-of-the-art unlearning method based on controlling model representations.
RMU reduces model performance on WMDP while maintaining general capabilities in
areas such as biology and computer science, suggesting that unlearning may be a
concrete path towards reducing malicious use from LLMs. We release our
benchmark and code publicly at https://wmdp.ai


  Analogical inference is a remarkable capability of human reasoning, and has
been used to solve hard reasoning tasks. Analogy based reasoning (AR) has
gained increasing interest from the artificial intelligence community and has
shown its potential in multiple machine learning tasks such as classification,
decision making and recommendation with competitive results. We propose a deep
learning (DL) framework to address and tackle two key tasks in AR: analogy
detection and solving. The framework is thoroughly tested on the Siganalogies
dataset of morphological analogical proportions (APs) between words, and shown
to outperform symbolic approaches in many languages. Previous work have
explored the behavior of the Analogy Neural Network for classification (ANNc)
on analogy detection and of the Analogy Neural Network for retrieval (ANNr) on
analogy solving by retrieval, as well as the potential of an autoencoder (AE)
for analogy solving by generating the solution word. In this article we
summarize these findings and we extend them by combining ANNr and the AE
embedding model, and checking the performance of ANNc as an retrieval method.
The combination of ANNr and AE outperforms the other approaches in almost all
cases, and ANNc as a retrieval method achieves competitive or better
performance than 3CosMul. We conclude with general guidelines on using our
framework to tackle APs with DL.


  Oscillatory behavior is a key property of many biological systems. The
Small-Gain Theorem (SGT) for input/output monotone systems provides a
sufficient condition for global asymptotic stability of an equilibrium and
hence its violation is a necessary condition for the existence of periodic
solutions. One advantage of the use of the monotone SGT technique is its
robustness with respect to all perturbations that preserve monotonicity and
stability properties of a very low-dimensional (in many interesting examples,
just one-dimensional) model reduction. This robustness makes the technique
useful in the analysis of molecular biological models in which there is large
uncertainty regarding the values of kinetic and other parameters. However,
verifying the conditions needed in order to apply the SGT is not always easy.
This paper provides an approach to the verification of the needed properties,
and illustrates the approach through an application to a classical model of
circadian oscillations, as a nontrivial ``case study,'' and also provides a
theorem in the converse direction of predicting oscillations when the SGT
conditions fail.


  The zeta-function of a complex variety is a power series whose nth
coefficient is the nth symmetric power of the variety, viewed as an element in
the Grothendieck ring of complex varieties. We prove that the zeta-function of
a surface is rational if and only if its Kodaira dimension is negative.


  In modern data analysis, random sampling is an efficient and widely-used
strategy to overcome the computational difficulties brought by large sample
size. In previous studies, researchers conducted random sampling which is
according to the input data but independent on the response variable, however
the response variable may also be informative for sampling. In this paper we
propose an adaptive sampling called the gradient-based sampling which is
dependent on both the input data and the output for fast solving of
least-square (LS) problems. We draw the data points by random sampling from the
full data according to their gradient values. This sampling is computationally
saving, since the running time of computing the sampling probabilities is
reduced to O(nd) where n is the full sample size and d is the dimension of the
input. Theoretically, we establish an error bound analysis of the general
importance sampling with respect to LS solution from full data. The result
establishes an improved performance of the use of our gradient- based sampling.
Synthetic and real data sets are used to empirically argue that the
gradient-based sampling has an obvious advantage over existing sampling methods
from two aspects of statistical efficiency and computational saving.


  PokerKit is an open-source Python library designed to overcome the
restrictions of existing poker game simulation and hand evaluation tools, which
typically support only a handful of poker variants and lack flexibility in game
state control. In contrast, PokerKit significantly expands this scope by
supporting an extensive array of poker variants and it provides a flexible
architecture for users to define their custom games. This paper details the
design and implementation of PokerKit, including its intuitive programmatic
API, multi-variant game support, and a unified hand evaluation suite across
different hand types. The flexibility of PokerKit allows for applications in
diverse areas, such as poker AI development, tool creation, and online poker
casino implementation. PokerKit's reliability has been established through
static type checking, extensive doctests, and unit tests, achieving 99% code
coverage. The introduction of PokerKit represents a significant contribution to
the field of computer poker, fostering future research and advanced AI
development for a wide variety of poker games. The source code is available at
https://github.com/uoftcprg/pokerkit


  We show that, whenever Gamma is a countable abelian group and Delta is a
finitely-generated subgroup of Gamma, a generic measure-preserving action of
Delta on a standard atomless probability space (X,mu) extends to a free
measure-preserving action of Gamma on (X,mu). This extends a result of Ageev,
corresponding to the case when Delta is infinite cyclic.


  Selection rules are often considered a hallmark of symmetry. When a symmetry
is broken, e.g., by an external perturbation, the system exhibits selection
rule deviations which are often analyzed by perturbation theory. Here, we
employ symmetry-breaking degrees of freedom as synthetic dimensions, to
demonstrate that symmetry-broken systems systematically exhibit a new class of
symmetries and selection rules. These selection rules determine the scaling of
a system's observables (to all orders in the strength of the symmetry-breaking
perturbation) as it transitions from symmetric to symmetry-broken. We
specifically analyze periodically driven (Floquet) systems subject to two
driving fields, where the first field imposes a spatio-temporal symmetry, and
the second field breaks it, imposing a symmetry in synthetic dimensions. We
tabulate the resulting synthetic symmetries for (2+1)D Floquet group symmetries
and derive the corresponding selection rules for high harmonic generation (HHG)
and above-threshold ionization (ATI). Finally, we observe experimentally HHG
selection rules imposed by symmetries in synthetic dimensions. The new class of
symmetries & selection rules extends the scope of existing symmetry breaking
spectroscopy techniques, opening new routes for ultrafast spectroscopy of
phonon-polarization, spin-orbit coupling, and more.


  We introduce a new multiscale restoration algorithm for images with few
photons counts and its use for denoising XMM data. We use a thresholding of the
wavelet space so as to remove the noise contribution at each scale while
preserving the multiscale information of the signal. Contrary to other
algorithms the signal restoration process is the same whatever the signal to
noise ratio is. Thresholds according to a Poisson noise process are indeed
computed analytically at each scale thanks to the use of the unnormalized Haar
wavelet transform. Promising preliminary results are obtained on X-ray data for
Abell 2163 with the computation of a temperature map.


  We describe the Hong-Ou-Mandel interference of two identical particles
evolving on a one-dimensional tight-binding lattice where a potential barrier
plays the role of a beam splitter. Careful consideration of the symmetries
underlying the two-particle interference effect allows us to reformulate the
problem in terms of ordinary wave interference in a Michelson interferometer.
This approach is easily generalized to the case where the particles interact,
and we compare the resulting analytical predictions for the bunching
probability to numerical simulations of the two-particle dynamics.


  Heavy meson production in nucleon-nucleon collisions is discussed within a
meson exchange model of hadronic interactions, paying special attention to the
basic dynamics that determine the behavior of the cross sections near the
threshold energy. The pp-->pp\phi reaction is discussed as an example of the
production of vector mesons in NN collisions. For the pseudoscalar meson
production, results for the \eta production in both the pp and pn collisions
are presented.


  This paper presents the basic principles of partition of unity systems and
B-splines. Analysis of these systems is performed using Fourier analysis,
multi-resolution analysis, and wavelet analysis.


  Consideration of a question of E. R. Berlekamp led Carlitz, Roselle, and
Scoville to give a combinatorial interpretation of the entries of certain
matrices of determinant~1 in terms of lattice paths. Here we generalize this
result by refining the matrix entries to be multivariate polynomials, and by
determining not only the determinant but also the Smith normal form of these
matrices. A priori the Smith form need not exist but its existence follows from
the explicit computation. It will be more convenient for us to state our
results in terms of partitions rather than lattice paths.


  In this paper, we study the semilinear wave equations with the inverse-square
potential. By transferring the original equation to a "fractional dimensional"
wave equation and analyzing the properties of its fundamental solution, we
establish a long-time existence result, for sufficiently small, spherically
symmetric initial data. Together with the previously known blow-up result, we
determine the critical exponent which divides the global existence and finite
time blow-up. Moreover, the sharp lower bounds of the lifespan are obtained,
except for certain borderline case. In addition, our technology allows us to
handle an extreme case for the potential, which has hardly been discussed in
literature.


  Dark Matter particles in the Galactic Center and halo can annihilate or decay
into a pair of neutrinos producing a monochromatic flux of neutrinos. The
spectral feature of this signal is unique and it is not expected from any
astrophysical production mechanism. Its observation would constitute a dark
matter smoking gun signal. We performed the first dedicated search with a
neutrino telescope for such signal, by looking at both the angular and energy
information of the neutrino events. To this end, a total of five years of
IceCube's DeepCore data has been used to test dark matter masses ranging from
10~GeV to 40~TeV. No significant neutrino excess was found and upper limits on
the annihilation cross section, as well as lower limits on the dark matter
lifetime, were set. The limits reached are of the order of $10^{-24}$~cm$^3/s$
for an annihilation and up to $10^{27}$ seconds for decaying Dark Matter. Using
the same data sample we also derive limits for dark matter annihilation or
decay into a pair of Standard Model charged particles.


  In a previous paper [arXiv:1604.05440], we studied certain random walks on
the hyperbolic graphs $X$ associated with the self-similar sets $K$, and showed
that the discrete energy ${\mathcal E}_X$ on $X$ has an induced energy form
${\mathcal E}_K$ on $K$ that is a Gagliardo-type integral. The domain of
${\mathcal E}_K$ is a Besov space $\Lambda^{\alpha, \beta/2}_{2,2}$ where
$\alpha$ is the Hausdorff dimension of $K$ and $\beta$ is a parameter
determined by the "return ratio" of the random walk. In this paper, we study
the functional relationship of ${\mathcal E}_X$ and ${\mathcal E}_K$. In
particular, we investigate the critical exponents of the $\beta$ in the domain
$\Lambda^{\alpha, \beta/2}_{2,2}$ in order for ${\mathcal E}_K$ to be a regular
Dirichlet form. We provide some criteria to determine the critical exponents
through the effective resistance of the random walk on $X$, and make use of
certain electrical network techniques to calculate the exponents for some
concrete examples.


  The Sun's magnetic field varies in multiple time scales. Observations show
that the minimum between cycles 24 and 25 was the second consecutive minimum
which was deeper and wider than several earlier minima. Since the active
regions observed at the Sun's surface are manifestations of the magnetic field
generated in the interior, it is crucial to investigate/understand the dynamics
below the surface. In this context, we report, by probing the solar interior
with helioseismic techniques applied to long-term oscillations data from the
Global Oscillation Network Group (GONG), that the seismic minima in deeper
layers have been occurring about a year earlier than that at the surface for
the last two consecutive solar cycles. Our findings also demonstrate a decrease
in strong magnetic fields at the base of the convection zone, the primary
driver of the surface magnetic activity. We conclude that the magnetic fields
located in the core and near-surface shear layers, in addition to the
tachocline fields, play an important role in modifying the oscillation
frequencies. This provides evidence that further strengthens the existence of a
relic magnetic field in the Sun's core since its formation.


  We perform a comprehensive study of the stellar population properties of
quiescent galaxies as a function of size and stellar mass to constrain the
physical mechanism governing the stellar mass assembly and the likely evolutive
scenarios that explain their growth in size. After selecting all the quiescent
galaxies from the ALHAMBRA survey by the dust-corrected stellar mass$-$colour
diagram, we built a shared sample of $\sim850$ quiescent galaxies with reliable
sizes from the HST. The stellar population properties were retrieved using the
SED-fitting code MUFFIT with various sets of composite stellar population
models. Age, formation epoch, metallicity, and extinction were studied on the
stellar mass$-$size plane as function of size through a Monte Carlo approach.
This accounted for uncertainties and degeneracy effects amongst stellar
population properties. The stellar population properties of quiescent galaxies
and their stellar mass and size since $z\sim1$ are correlated. At fixed stellar
mass, the more compact the quiescent galaxy, the older and richer in metals it
is ($1$Gyr and $0.1$dex, respectively). In addition, more compact galaxies may
present slight lower extinctions than their more extended counterparts at the
same stellar mass ($<0.1$ mag). By means of studying constant regions of
stellar population properties across the stellar mass$-$size plane, we obtained
empirical relations to constrain the physical mechanism that governs the
stellar mass assembly of the form $M_\star \propto r_\mathrm{c}^\alpha$, where
$\alpha$ amounts to $0.50-0.55 \pm 0.09$. There are indications that support
the idea that the velocity dispersion is tightly correlated with the stellar
content of galaxies. The mechanisms driving the evolution of stellar
populations can therefore be partly linked to the dynamical properties of
galaxies, along with their gravitational potential.


  Superchiral field is highly important for ultrasensitive detection of chiral
objects and has been intensively explored. Despite the progress, the
construction of electromagnetic field in achiral nanostructures with giant
chirality (C) is fundamentally restricted. Here, we demonstrate a novel
approach to construct superchiral field in achiral dielectric metasurfaces. Due
to the quantum spin-hall effect, each symmetry-protected bound state in the
continuum (BIC) exhibits the ability to support a superchiral field in vicinity
of \Gamma point. By merging two BICs with orthogonal polarizations, all the
criteria for a superchiral field are satisfied and the dramatic enhancement of
chirality becomes more robust. Using typical photonic crystal slabs, we have
produced a superchiral field with enhancement factor (C/C_CPL) orders of
magnitude higher than state-of-the-art in nanostructures. By further
introducing active chiral medium, a chiral mode splitting associated with giant
enhancement of circular dichroism (CD) has been formed by the chiral
light-matter interaction.


  The problem of estimating single- and multi-dimensional integrals, with or
without end-point singularities, is prevalent in all fields of scientific
research, and in particular in physics. Although tanh-sinh quadrature is known
to handle most of these cases excellently, its use is not widely spread among
physicists. Moreover, while most calculations are limited by the use of
finite-precision floating-point arithmetic, similar considerations for
tanh-sinh quadrature are mostly lacking in literature, where infinite-precision
floating-point numbers are often assumed. Also little information is available
on the application of tanh-sinh quadrature to multiple integration.
  We have investigated the risks and limitations associated with
limited-precision floating-point numbers when using tanh-sinh quadrature for
both single and multiple integration, while obtaining excellent convergence
rates. In addition, this paper provides recommendations for a straightforward
implementation using limited-precision floating-point numbers and for avoiding
numerical instabilities.


  Outer Billiards is a geometrically inspired dynamical system based on a
convex shape in the plane.
  When the shape is a polygon, the system has a combinatorial flavor. In the
polygonal case, there is a natural acceleration of the map, a first return map
to a certain strip in the plane. The arithmetic graph is a geometric encoding
of the symbolic dynamics of this first return map.
  In the case of the regular octagon, the case we study, the arithmetic graphs
associated to periodic orbits are polygonal paths in R^8. We are interested in
the asymptotic shapes of these polygonal paths, as the period tends to
infinity. We show that the rescaled limit of essentially any sequence of these
graphs converges to a fractal curve that simultaneously projects one way onto a
variant of the Koch snowflake and another way onto a variant of the Sierpinski
carpet. In a sense, this gives a complete description of the asymptotic
behavior of the symbolic dynamics of the first return map.
  What makes all our proofs work is an efficient (and basically well known)
renormalization scheme for the dynamics.


  We present a simple finite element formulation of mass-consistent
approximation, and a fast multigrid iterative method with adaptive
semicoarsening, which maintains the convergence of the iterations over a range
of grids and penalty coefficients. The method is designed to run in each time
step of WRF-SFIRE and replace the interpolation from the atmospheric mesh to
the fire mesh by a diagnostic model of the air flow over a fine-scale terrain.


  Elastic matrix distortion around a growing inclusion of a new phase is
analyzed and the associated contribution to the Gibbs free energy is
considered. The constant-composition transformation from the parent to product
phase is considered within the frame of Landau theory of phase transitions. The
volume misfit between the inclusion and matrix is assumed to originate from the
transformation volume change coupled with the phenomenological order parameter.
The minimization of free energy with respect to the volume change and order
parameter gives the dependence of Gibbs energy on the volume fraction of the
product phase. The transformation proceeds in a finite temperature region with
the equilibrium volume fraction dependent on temperature rather than at a fixed
temperature as it would be expected for the first-order transition. The
activation processes are shown to be irrelevant and the transformation kinetics
is found to be fluctuationless.


This paper has been withdrawn by the authors for future revision.


  Mott transitions in real materials are first order and almost always
associated with lattice distortions, both features promoting the emergence of
nanotextured phases. This nanoscale self-organization creates spatially
inhomogeneous regions, which can host and protect transient non-thermal
electronic and lattice states triggered by light excitation.
  Here, we combine time-resolved X-ray microscopy with a Landau-Ginzburg
functional approach for calculating the strain and electronic real-space
configurations. We investigate V$_2$O$_3$, the archetypal Mott insulator in
which nanoscale self-organization already exists in the low-temperature
monoclinic phase and strongly affects the transition towards the
high-temperature corundum metallic phase. Our joint experimental-theoretical
approach uncovers a remarkable out-of-equilibrium phenomenon: the photo-induced
stabilisation of the long sought monoclinic metal phase, which is absent at
equilibrium and in homogeneous materials, but emerges as a metastable state
solely when light excitation is combined with the underlying nanotexture of the
monoclinic lattice.


  Let $(A,\mathfrak{m})$ be a complete intersection with $k = A/\mathfrak{m}$
algebraically closed. Let CMS(A) be the stable category of maximal CM
$A$-modules. For a large class of thick subcategories $\mathcal{S}$ of CMS(A)
we show that there is a theory of support varieties for the Verdier quotient
$\mathcal{T} = $ CMS(A)$/\mathcal{S}$. As an application we show that the
analogous version of Auslander-Reiten conjecture, Murthys result,
Avramov-Buchweitz result on symmetry of vanishing of cohomology holds for
$\mathcal{T}$.


  The Special Issue on "Modified Gravity Approaches to the Tensions of
$\Lambda$CDM"} in the Universe journal tackles significant challenges faced by
the $\Lambda$CDM model, including discrepancies in the Hubble constant, growth
rate of structures, and cosmological anisotropies. These issues suggest
foundational cracks in the model, raising questions about the validity of
General Relativity, dark energy, and cosmological principles at large scales.
This collection brings together leading researchers to delve into Modified
Gravity theories as potential solutions. Covering approaches from Scalar-Tensor
theories to $f(R,T)$ gravity and beyond, each contribution presents innovative
research aimed at addressing the limitations of the $\Lambda$CDM model. This
Special Issue not only highlights the theoretical and empirical strengths of
Modified Gravity models but also opens avenues for future investigations,
emphasizing the synergy between theoretical advancements and observational
evidence to deepen our cosmological understanding.


  We study the phase diagram and quantum critical region of one of the
fundamental models for electronic correlations: the periodic Anderson model.
Employing the recently developed dynamical vertex approximation, we find a
phase transition between a zero-temperature antiferromagnetic insulator and a
Kondo insulator. In the quantum critical region, we determine a critical
exponent $\gamma\!=\!2$ for the antiferromagnetic susceptibility. At higher
temperatures, we have free spins with $\gamma\!=\!1$ instead, whereas at lower
temperatures, there is an even stronger increase and suppression of the
susceptibility below and above the quantum critical point, respectively.


  We describe a generative network model of the architecture of the enteric
nervous system (ENS) in the colon employing data from images of human and mouse
tissue samples obtained through confocal microscopy. Our models combine spatial
point pattern analysis with graph generation to characterize the spatial and
topological properties of the ganglia (clusters of neurons and glial cells),
the inter-ganglionic connections, and the neuronal organization within the
ganglia. We employ a hybrid hardcore-Strauss process for spatial patterns and a
planar random graph generation for constructing the spatially embedded network.
We show that our generative model may be helpful in both basic and
translational studies, and it is sufficiently expressive to model the ENS
architecture of individuals who vary in age and health status. Increased
understanding of the ENS connectome will enable the use of neuromodulation
strategies in treatment and clarify anatomic diagnostic criteria for people
with bowel motility disorders.


  Electro-optic phase modulators are critical components in modern
communication, microwave photonic, and quantum photonic systems. Important for
these applications is to achieve modulators with low half-wave voltage at high
frequencies. Here we demonstrate an integrated phase modulator, based on a
thin-film lithium niobate platform, that simultaneously features small on-chip
loss (~ 1 dB) and low half-wave voltage over a large spectral range (3.5 - 4.5
V at 5 - 40 GHz). By driving the modulator with a strong 30-GHz microwave
signal corresponding to around four half-wave voltages, we generate an optical
frequency comb consisting of over 40 sidebands spanning 10 nm in the telecom
L-band. The high electro-optic performance combined with the high RF
power-handling ability (3.1 W) of our integrated phase modulator are crucial
for future photonics and microwave systems.


  We analyse the classical and quantum geometry of the Barrett-Crane spin foam
model for four dimensional quantum gravity, explaining why it has to be
considering as a covariant realization of the projector operator onto physical
quantum gravity states. We discuss how causality requirements can be
consistently implemented in this framework, and construct causal transiton
amplitudes between quantum gravity states, i.e. realising in the spin foam
context the Feynman propagator between states. The resulting causal spin foam
model can be seen as a path integral quantization of Lorentzian first order
Regge calculus, and represents a link between several approaches to quantum
gravity as canonical loop quantum gravity, sum-over-histories formulations,
dynamical triangulations and causal sets. In particular, we show how the
resulting model can be rephrased within the framework of quantum causal sets
(or histories).


  In concurrent systems, some form of synchronisation is typically needed to
achieve data-race freedom, which is important for correctness and safety. In
actor-based systems, messages are exchanged concurrently but executed
sequentially by the receiving actor. By relying on isolation and non-sharing,
an actor can access its own state without fear of data-races, and the internal
behavior of an actor can be reasoned about sequentially.
  However, actor isolation is sometimes too strong to express useful patterns.
For example, letting the iterator of a data-collection alias the internal
structure of the collection allows a more efficient implementation than if each
access requires going through the interface of the collection. With full
isolation, in order to maintain sequential reasoning the iterator must be made
part of the collection, which bloats the interface of the collection and means
that a client must have access to the whole data-collection in order to use the
iterator.
  In this paper, we propose a programming language construct that enables a
relaxation of isolation but without sacrificing sequential reasoning. We
formalise the mechanism in a simple lambda calculus with actors and passive
objects, and show how an actor may leak parts of its internal state while
ensuring that any interaction with this data is still synchronised.


  A possibility to give strong mathematical definitions of outliers and heavy
tailed distributions or their modification is discussed. Some alternatives for
the notion of tail index are proposed. Key words: outliers, heavy tails, tail
index.


  The early Universe is a precious probe of the birth of primordial objects,
first star formation events and consequent production of photons and heavy
elements. Higher-order corrections to the cosmological linear perturbation
theory predicts the formation of coherent supersonic gaseous streaming motions
at decoupling time. These bulk flows impact the gas cooling process and
determine a cascade effect on the whole baryon evolution. By analytical
estimates and N-body hydrodynamical chemistry numerical simulations including
atomic and molecular evolution, gas cooling, star formation, feedback effects
and metal spreading for individual species from different stellar populations
according to the proper yields and lifetimes, we discuss the role of these
primordial bulk flows at the end of the dark ages and their detectable impacts
during the first Gyr in view of the upcoming SKA mission. Early bulk flows can
inhibit molecular gas cooling capabilities, suppressing star formation, metal
spreading and the abundance of small primordial galaxies in the infant
Universe. This can determine a delay in the re-ionization process and in the
heating of neutral hydrogen making the observable HI signal during cosmic
evolution patchier and noisier. The planned SKA mission will represent a major
advance over existing instruments, since it will be able to probe the effects
on HI 21cm at z ~ 6-20 and on molecular line emissions from first collapsing
sites at z ~ 20-40. Therefore, it will be optimal to address the effects of
primordial streaming motions on early baryon evolution and to give constraints
on structure formation in the first Gyr.


  The investigation of dynamical processes on networks has been one focus for
the study of contagion processes. It has been demonstrated that contagions can
be used to obtain information about the embedding of nodes in a Euclidean
space. Specifically, one can use the activation times of threshold contagions
to construct contagion maps as a manifold-learning approach. One drawback of
contagion maps is their high computational cost. Here, we demonstrate that a
truncation of the threshold contagions may considerably speed up the
construction of contagion maps. Finally, we show that contagion maps may be
used to find an insightful low-dimensional embedding for single-cell
RNA-sequencing data in the form of cell-similarity networks and so reveal
biological manifolds. Overall, our work makes the use of contagion maps as
manifold-learning approaches on empirical network data more viable.


  We present the rapidity distribution of the Higgs boson produced through
bottom quark annihilation at third order in QCD using the threshold
approximation. We provide a framework, based on the factorization properties of
the QCD amplitudes along with Sudakov resummation and the renormalization group
invariance, that allows one to perform the computation of the threshold
corrections in a consistent, systematic and accurate way. The recent results on
threshold N$^3$LO correction in QCD for the Drell-Yan production and on three
loop QCD correction to Higgs form factor with bottom anti-bottom quark are used
to achieve this task. We also demonstrate the numerical impact of these
corrections at the LHC.


  We study the behavior of the random walk on the infinite cluster of
independent long range percolation in dimensions $d=1,2$, where $x$ and $y$ a
re connected with probability $\sim\beta/\|x-y\|^{-s}$. We show that when
$d<s<2d$ the walk is transient, and when $s\geq 2d$, the walk is recurrent. The
proof of transience is based on a renormalization argument. As a corollary of
this renormalization argument, we get that for every dimension $d$, if
$d<s<2d$, then critical percolation has no infinite clusters. This result is
extended to the free random cluster model. A second corollary is that when
$d\geq 2$ and $d<s<2d$ we can erase all long enough bonds and still have an
infinite cluster. The proof of recurrence in two dimensions is based on general
stability results for recurrence in random electrical networks. In particular,
we show that i.i.d. conductances on a recurrent graph of bounded degree yield a
recurrent electrical network.


  When an elastic tube reinforced with helical fibres is inflated, its ends
rotate. In large deformations, the amount and chirality of rotation is highly
non-trivial, as it depends on the choice of strain-energy density and the
arrangements of the fibres. For anisotropic hyperelastic tubes where the
material parameters are single-valued constants, the problem has been
satisfactorily addressed. However, in many systems, the material parameters are
not precisely known, and it is therefore more appropriate to treat them as
random variables. The problem is then to understand chirality in a
probabilistic framework. Here, we develop a procedure for examining the elastic
responses of a hyperelastic cylindrical tube of stochastic anisotropic
material, where the material parameters are spatially-independent random
variables defined by probability density functions. The tube is subjected to
uniform dead loading consisting of internal pressure, axial tension and torque.
Assuming that the tube wall is thin and that the resulting deformation is the
combined inflation, extension and torsion from the reference circular
cylindrical configuration to a deformed circular cylindrical state, we derive
the probabilities of radial expansion or contraction, and of right-handed or
left-handed torsion. We refer to these stochastic behaviours as `likely
inflation' and `likely chirality', respectively.


  Let $A,B$ be C*-algebras, $B_A(0;r)$ the open ball in $A$ centered at $0$
with radius $r>0$, and $H:B_A(0;r)\to B$ an orthogonally additive holomorphic
map. If $H$ is zero product preserving on positive elements in $B_A(0;r)$, we
show, in the commutative case when $A=C_0(X)$ and $B=C_0(Y)$, that there exist
weight functions $h_n$'s and a symbol map $\varphi: Y\to X$ such that $$
H(f)=\sum_{n\geq1} h_n (f\circ\varphi)^n, \quad\forall f\in B_{C_0(X)}(0;r). $$
In the general case, we show that if $H$ is also conformal then there exist
central multipliers $h_n$'s of $B$ and a surjective Jordan isomorphism $J: A\to
B$ such that $$ H(a) = \sum_{n\geq1} h_n J(a)^n, \quad\forall a\in B_A(0;r). $$
If, in addition, $H$ is zero product preserving on the whole $B_A(0;r)$, then
$J$ is an algebra isomorphism. %Similar conclusions hold for orthogonally
additive $n$-homogeneous polynomials which are $n$-isometries.


  We focus on Optimal Transport PDE on the unit sphere $\mathbb{S}^2$ with a
particular type of cost function $c(x,y) = F(x \cdot y, x \cdot \hat{e}, y
\cdot \hat{e})$ which we call cost functions with preferential direction, where
$\hat{e} \in \mathbb{S}^2$. This type of cost function arises in an optics
application which we call the point-to-point reflector problem. We define basic
hypotheses on the cost functions with preferential direction that will allow
for the Ma-Trudinger-Wang (MTW) conditions to hold and construct a regularity
theory for such cost functions. For the point-to-point reflector problem, we
show that the negative cost-sectional curvature condition does not hold. We
will nevertheless prove the existence of a unique solution of the
point-to-point reflector problem, up to a constant, provided that the source
and target intensity are "close enough".


  We investigate the mechanical properties of amorphous polymers by means of
coarse-grained simulations and nonaffine lattice dynamics theory. A small
increase of polymer chain bending stiffness leads first to softening of the
material, while hardening happens only upon further strengthening of the
backbones. This nonmonotonic variation of the storage modulus $G'$ with bending
stiffness is caused by a competition between additional resistance to
deformation offered by stiffer backbones and decreased density of the material
due to a necessary decrease in monomer-monomer coordination. This
counter-intuitive finding suggests that the strength of polymer glasses may in
some circumstances be enhanced by softening the bending of constituent chains.


  The Hamiltonian analysis for a 3-dimensional connection dynamics of
$\frak{so}(1,2)$, spanned by $\{L_{-+},L_{-2},L_{+2}\}$ instead of $\{L_{01},
L_{02}, L_{12}\}$, is first conducted in a Bondi-like coordinate system.The
symmetry of the system is clearly presented. A null coframe with 3 independent
variables and 9 connection coefficients are treated as basic configuration
variables. All constraints and their consistency conditions, the solutions of
Lagrange multipliers as well as the equations of motion are presented. There is
no physical degree of freedom in the system. The Ba\~nados-Teitelboim-Zanelli
(BTZ) spacetime is discussed as an example to check the analysis. Unlike the
ADM formalism, where only non-degenerate geometries on slices are dealt with
and the Ashtekar formalism, where non-degenerate geometries on slices are
mainly concerned though the degenerate geometries may be studied as well, in
the present formalism the geometries on the slices are always degenerate though
the geometries for the spacetime are not degenerate.


  Understanding the radii of massive stars throughout their evolution is
important to answering numerous questions about stellar physics, from binary
interactions on the main sequence to the pre-supernova radii. One important
factor determining a star's radius is the fraction of its mass in elements
heavier than Helium (metallicity, $Z$). However, the metallicity enters stellar
evolution through several distinct microphysical processes, and which dominates
can change throughout stellar evolution and with the overall magnitude of $Z$.
We perform a series of numerical experiments with 15M$_{\odot}$ MESA models
computed doubling separately the metallicity entering the radiative opacity,
the equation of state, and the nuclear reaction network to isolate the impact
of each on stellar radii. We explore separately models centered around two
metallicity values: one near solar $Z=0.02$ and another sub-solar
$Z\sim10^{-3}$, and consider several key epochs from the end of the main
sequence to core carbon depletion. We find that the metallicity entering the
opacity dominates at most epochs for the solar metallicity models, contributing
to on average $\sim$60 - 90% of the total change in stellar radius. Nuclear
reactions have a larger impact ($\sim$50 - 70%) during most epochs in the
subsolar $Z$ models. The methodology introduced here can be employed more
generally to propagate known microphysics errors into uncertainties on
macrophysical observables including stellar radii.


  In this paper we focus on crystal surfaces led out of equilibrium by a growth
or erosion process. As a consequence of that the surface may undergo
morphological instabilities and develop a distinct structure: ondulations,
mounds or pyramids, bunches of steps, ripples. The typical size of the emergent
pattern may be fixed or it may increase in time through a coarsening process
which in turn may last forever or it may be interrupted at some relevant length
scale. We study dynamics in three different cases, stressing the main physical
ingredients and the main features of coarsening: a kinetic instability, an
energetic instability, and an athermal instability.


  The status of W and Z cross-section and width measurements from the CDF and
D0 experiments is reviewed. Recent results that are discussed: the
cross-section for Z production times the branching ratio to tau pairs, the
rapidity and transverse momentum distributions of Z production in the electron
channel, and the direct measurements of the W width and the Z invisible width;
the latter from an analysis of events with large missing transverse energy and
one or more energetic jets.


  We show that point-like defect model of glasses cannot explain thermodynamic
properties of glass-formers, as for example the excess specific heat close to
the glass transition, contrary to the claim of J.P. Garrahan, D. Chandler
[Proc. Natl. Acad. Sci. 100, 9710 (2003)]. More general models and approaches
in terms of extended defects are also discussed.


  The goal of creating Artificial General Intelligence (AGI) -- or in other
words of creating Turing machines (modern computers) that can behave in a way
that mimics human intelligence -- has occupied AI researchers ever since the
idea of AI was first proposed. One common theme in these discussions is the
thesis that the ability of a machine to conduct convincing dialogues with human
beings can serve as at least a sufficient criterion of AGI. We argue that this
very ability should be accepted also as a necessary condition of AGI, and we
provide a description of the nature of human dialogue in particular and of
human language in general against this background. We then argue that it is for
mathematical reasons impossible to program a machine in such a way that it
could master human dialogue behaviour in its full generality. This is (1)
because there are no traditional explicitly designed mathematical models that
could be used as a starting point for creating such programs; and (2) because
even the sorts of automated models generated by using machine learning, which
have been used successfully in areas such as machine translation, cannot be
extended to cope with human dialogue. If this is so, then we can conclude that
a Turing machine also cannot possess AGI, because it fails to fulfil a
necessary condition thereof. At the same time, however, we acknowledge the
potential of Turing machines to master dialogue behaviour in highly restricted
contexts, where what is called ``narrow'' AI can still be of considerable
utility.


  A low-temperature intervening metallic regime arising in the two-dimensional
superconductor-insulator transition challenges our understanding of electronic
fluids. Here we develop a gauge theory revealing that this emergent anomalous
metal is a bosonic topological insulator where bulk transport is suppressed by
mutual statistics interactions between out-of-condensate Cooper pairs and
vortices and the longitudinal conductivity is mediated by symmetry-protected
gapless edge modes. We explore the magnetic-field-driven
superconductor-insulator transition in a niobium titanium nitride device and
find marked signatures of a bosonic topological insulator behavior of the
intervening regime with the saturating resistance. The observed
superconductor-anomalous metal and insulator-anomalous metal dual phase
transitions exhibit quantum Berezinskii-Kosterlitz-Thouless criticality in
accord with the gauge theory.


  We experimentally study a new kind of parametric noise that is initiated from
signal scattering and enhanced through optical parametric amplification. Such
scattering noise behaves similarly to the parametric super-fluorescence in the
spatial domain, yet is typically much stronger. In the time domain, it inherits
the chirp of signal pulses and can be well compressed. We demonstrate that this
scattering-initiated parametric noise has little influence on the amplified
pulse contrast but can degrade the conversion efficiency substantially.


  We develop a non-local dielectric response theory to describe the temperature
dependence of exciton lifetime in metal-semiconductor heterostructures.
Coupling between excitons and surface plasmons results in a strongly
nonmonotonous behaviour of exciton radiative decay rate versus temperature.
Tuning the plasmon frequency one can control the efficiency of exciton emission
of light.


  Stochastic-gradient-based optimization has been a core enabling methodology
in applications to large-scale problems in machine learning and related areas.
Despite the progress, the gap between theory and practice remains significant,
with theoreticians pursuing mathematical optimality at a cost of obtaining
specialized procedures in different regimes (e.g., modulus of strong convexity,
magnitude of target accuracy, signal-to-noise ratio), and with practitioners
not readily able to know which regime is appropriate to their problem, and
seeking broadly applicable algorithms that are reasonably close to optimality.
To bridge these perspectives it is necessary to study algorithms that are
adaptive to different regimes. We present the stochastically controlled
stochastic gradient (SCSG) method for composite convex finite-sum optimization
problems and show that SCSG is adaptive to both strong convexity and target
accuracy. The adaptivity is achieved by batch variance reduction with adaptive
batch sizes and a novel technique, which we referred to as geometrization,
which sets the length of each epoch as a geometric random variable. The
algorithm achieves strictly better theoretical complexity than other existing
adaptive algorithms, while the tuning parameters of the algorithm only depend
on the smoothness parameter of the objective.


  A key capability in managing patent applications or a patent portfolio is
comparing claims to other text, e.g. a patent specification. Because the
language of claims is different from language used elsewhere in the patent
application or in non-patent text, this has been challenging for computer based
natural language processing. We test two new LLM-based approaches and find that
both provide substantially better performance than previously published values.
The ability to match dense information from one domain against much more
distributed information expressed in a different vocabulary may also be useful
beyond the intellectual property space.


  The emerging class of instance-optimized systems has shown potential to
achieve high performance by specializing to a specific data and query
workloads. Particularly, Machine Learning (ML) techniques have been applied
successfully to build various instance-optimized components (e.g., learned
indexes). This paper investigates to leverage ML techniques to enhance the
performance of spatial indexes, particularly the R-tree, for a given data and
query workloads. As the areas covered by the R-tree index nodes overlap in
space, upon searching for a specific point in space, multiple paths from root
to leaf may potentially be explored. In the worst case, the entire R-tree could
be searched. In this paper, we define and use the overlap ratio to quantify the
degree of extraneous leaf node accesses required by a range query. The goal is
to enhance the query performance of a traditional R-tree for high-overlap range
queries as they tend to incur long running-times. We introduce a new AI-tree
that transforms the search operation of an R-tree into a multi-label
classification task to exclude the extraneous leaf node accesses. Then, we
augment a traditional R-tree to the AI-tree to form a hybrid "AI+R"-tree. The
"AI+R"-tree can automatically differentiate between the high- and low-overlap
queries using a learned model. Thus, the "AI+R"-tree processes high-overlap
queries using the AI-tree, and the low-overlap queries using the R-tree.
Experiments on real datasets demonstrate that the "AI+R"-tree can enhance the
query performance over a traditional R-tree by up to 500%.


  Inspired by human conscious planning, we propose Skipper, a model-based
reinforcement learning framework utilizing spatio-temporal abstractions to
generalize better in novel situations. It automatically decomposes the given
task into smaller, more manageable subtasks, and thus enables sparse
decision-making and focused computation on the relevant parts of the
environment. The decomposition relies on the extraction of an abstracted proxy
problem represented as a directed graph, in which vertices and edges are
learned end-to-end from hindsight. Our theoretical analyses provide performance
guarantees under appropriate assumptions and establish where our approach is
expected to be helpful. Generalization-focused experiments validate Skipper's
significant advantage in zero-shot generalization, compared to some existing
state-of-the-art hierarchical planning methods.


  By means of high-pressure resistivity measurements on single crystals, we
investigate the charge transport properties of Cu$_x$PdTe$_2$, notable for the
combination of topological type-II Dirac semimetallic properties with
superconductivity up to $T_c = 2.5$ K. In both cases of pristine ($x = 0$) and
intercalated ($x=0.05$) samples, we find an unconventional $T^4$ power law
behavior of the low-temperature resistivity visible up to $\sim$40 K and
remarkably stable under pressure up to 8.2 GPa. This observation is explained
by the low carrier density $n$, which strongly reduces the $k$-region available
for electron-phonon scattering, as previously reported in other low-$n$
two-dimensional systems, such as multilayer graphene and semiconductor
heterostructures. Our data analysis complemented by specific heat measurements
and supported by previous quantum oscillation studies and \textit{ab initio}
calculations suggests a scenario of one-band charge transport. Within this
scenario, our analysis yields a large value of transport electron-phonon
coupling constant $\lambda_{tr} = 1.2$ at ambient pressure that appears to be
strongly enhanced by pressure assuming a constant effective mass.


  We consider the problem of simultaneously clustering and learning a linear
representation of data lying close to a union of low-dimensional manifolds, a
fundamental task in machine learning and computer vision. When the manifolds
are assumed to be linear subspaces, this reduces to the classical problem of
subspace clustering, which has been studied extensively over the past two
decades. Unfortunately, many real-world datasets such as natural images can not
be well approximated by linear subspaces. On the other hand, numerous works
have attempted to learn an appropriate transformation of the data, such that
data is mapped from a union of general non-linear manifolds to a union of
linear subspaces (with points from the same manifold being mapped to the same
subspace). However, many existing works have limitations such as assuming
knowledge of the membership of samples to clusters, requiring high sampling
density, or being shown theoretically to learn trivial representations. In this
paper, we propose to optimize the Maximal Coding Rate Reduction metric with
respect to both the data representation and a novel doubly stochastic cluster
membership, inspired by state-of-the-art subspace clustering results. We give a
parameterization of such a representation and membership, allowing efficient
mini-batching and one-shot initialization. Experiments on CIFAR-10, -20, -100,
and TinyImageNet-200 datasets show that the proposed method is much more
accurate and scalable than state-of-the-art deep clustering methods, and
further learns a latent linear representation of the data.


  This paper proposes a novel fuzzy cascaded Proportional-Derivative (PD)
controller for under-actuated single-link flexible joint manipulators. The
original flexible joint system is considered as two coupled $2^{nd}$-order
sub-systems. The proposed controller is composed of two cascaded PD controllers
and two fuzzy logic regulators (FLRs). The first (virtual) PD controller is
used to generate desired control input that stabilizes the first $2^{nd}$-order
sub-system. Solving the equation by considering the coupling terms as design
variables, the reference signal is generated for the second sub-system. Then
through simple compensation design, together with the second PD controller, the
cascaded PD controller is derived. In order to further improve the performance,
two FLRs are implemented that adaptively tune the parameters of PD controllers.
Under natural assumptions, the cascaded fuzzy PD controller is proved to
possess locally asymptotic stability. All the offline tuning processes are
completed data-efficiently by Bayesian Optimization. The results in simulation
illustrate the stability and validity of our proposed method. Besides, the idea
of cascaded PD controller presented here may be extended as a novel control
method for other under-actuated systems, and the stability analysis renders a
new perspective towards the stability proof of all other fuzzy-enhanced PID
controllers.


  Let A=(a_(ij)) be the generic n by n circulant matrix given by
a_(ij)=x_(i+j), with subscripts on x interpreted mod n. Define d(n) (resp.
p(n)) to be the number of terms in the determinant (resp. permanent) of A. The
function p(n) is well-known and has several combinatorial interpretations. The
function d(n), on the other hand, has not been studied previously. We show that
when n is a prime power, d(n)=p(n). The proof uses symmetric functions.


  Like clustering analysis, community detection aims at assigning nodes in a
network into different communities. Fdp is a recently proposed density-based
clustering algorithm which does not need the number of clusters as prior input
and the result is insensitive to its parameter. However, Fdp cannot be directly
applied to community detection due to its inability to recognize the community
centers in the network. To solve the problem, a new community detection method
(named IsoFdp) is proposed in this paper. First, we use Isomap technique to map
the network data into a low dimensional manifold which can reveal diverse
pair-wised similarity. Then Fdp is applied to detect the communities in
networks. An improved partition density function is proposed to select the
proper number of communities automatically. We test our method on both
synthetic and real-world networks, and the results demonstrate the
effectiveness of our algorithm over the state-of-the-art methods.


  The emerging trend of AR/VR places great demands on 3D content. However, most
existing software requires expertise and is difficult for novice users to use.
In this paper, we aim to create sketch-based modeling tools for user-friendly
3D modeling. We introduce Reality3DSketch with a novel application of an
immersive 3D modeling experience, in which a user can capture the surrounding
scene using a monocular RGB camera and can draw a single sketch of an object in
the real-time reconstructed 3D scene. A 3D object is generated and placed in
the desired location, enabled by our novel neural network with the input of a
single sketch. Our neural network can predict the pose of a drawing and can
turn a single sketch into a 3D model with view and structural awareness, which
addresses the challenge of sparse sketch input and view ambiguity. We conducted
extensive experiments synthetic and real-world datasets and achieved
state-of-the-art (SOTA) results in both sketch view estimation and 3D modeling
performance. According to our user study, our method of performing 3D modeling
in a scene is $>$5x faster than conventional methods. Users are also more
satisfied with the generated 3D model than the results of existing methods.


  We use the self-consistent mean-field theory to discuss the ground state and
decay properties of $\Lambda$ hypernuclei. We first discuss the deformation of
$\Lambda$ hypernuclei using the relativistic mean-field (RMF) approach. We show
that, although most of hypernuclei have a similar deformation parameter to the
core nucleus, the shape of $^{28}$Si is drastically altered, from oblately
deformed to spherical, if a $\Lambda$ particle is added to this nucleus. We
then discuss the pionic weak decay of neutron-rich $\Lambda$ hypernuclei using
the Skyrme Hartree-Fock + BCS method. We show that, for a given isotope chain,
the decay rate increases as a function of mass number, due to the strong
neutron-proton interaction.


  We aim for composing algorithmic music in an interactive way with multiple
participants. To this end we have developed an interpreter for a sub-language
of the non-strict functional programming language Haskell that allows the
modification of a program during its execution. Our system can be used both for
musical live-coding and for demonstration and education of functional
programming.


  The Vector Spectromagnetograph (VSM) instrument on the Synoptic Optical
Long-term Investigations of the Sun (SOLIS) telescope is designed to obtain
high-quality magnetic field observations in both the photosphere and
chromosphere by measuring the Zeeman-induced polarization of spectral lines.
With 1$^{\prime \prime}$ spatial resolution (1.14$^{\prime \prime}$ before
2010) and 0.05\AA\ spectral resolution, the VSM provides, among other products,
chromospheric full-disk magnetograms using the CaII 854.2 nm spectral line and
both photospheric full-disk vector and longitudinal magnetograms using the FeI
630.15 nm line. Here we describe the procedure used to compute daily weighted
averages of the photospheric radial polar magnetic field at different latitude
bands from SOLIS/VSM longitudinal full-disk observations. Time series of these
measurements are publicly available from the SOLIS website at
http://solis.nso.edu/0/vsm/vsm\_plrfield.html. Future plans include the
calculation of the mean polar field strength from SOLIS/VSM chromospheric
observations and the determination of the {\it true} radial polar field from
SOLIS/VSM full-Stokes measurements.


  Aqueous colloidal Laponite clay suspensions transform spontaneously to a soft
solid-like arrested state as its aging or waiting time increases. This article
reports the rapid transformation of aqueous Laponite suspensions into soft
solids due to the application of a DC electric field. A substantial increase in
the speed of solidification at higher electric field strengths is also
observed. The electric field is applied across two parallel brass plates
immersed in the Laponite suspension. The subsequent solidification that takes
place on the surface of the positive electrode is attributed to the dominant
negative surface charges on the Laponite particles and the associated
electrokinetic phenomena. With increasing electric field strength, a dramatic
increase is recorded in the elastic moduli of the samples. These electric field
induced Laponite soft solids demonstrate all the typical rheological
characteristics of soft glassy materials. They also exhibit a two-step shear
melting process similar to that observed in attractive soft glasses. The
microstructures of the samples, studied using cryo-scanning electron microscopy
(SEM), are seen to consist of percolated network gel-like structures, with the
connectivity of the gel network increasing with increasing electric field
strengths. In comparison with salt induced gels, the electric field induced
gels studied here are mechanically stronger and more stable over longer periods
of time


  Data-target pairing is an important step towards multi-target localization
for the intelligent operation of unmanned systems. Target localization plays a
crucial role in numerous applications, such as search, and rescue missions,
traffic management and surveillance. The objective of this paper is to present
an innovative target location learning approach, where numerous machine
learning approaches, including K-means clustering and supported vector machines
(SVM), are used to learn the data pattern across a list of spatially
distributed sensors. To enable the accurate data association from different
sensors for accurate target localization, appropriate data pre-processing is
essential, which is then followed by the application of different machine
learning algorithms to appropriately group data from different sensors for the
accurate localization of multiple targets. Through simulation examples, the
performance of these machine learning algorithms is quantified and compared.


  In this paper we study the personalized book recommender system in a
child-robot interactive environment. Firstly, we propose a novel text search
algorithm using an inverse filtering mechanism that improves the efficiency.
Secondly, we propose a user interest prediction method based on the Bayesian
network and a novel feedback mechanism. According to children's fuzzy language
input, the proposed method gives the predicted interests. Thirdly, the domain
specific synonym association is proposed based on word vectorization, in order
to improve the understanding of user intention. Experimental results show that
the proposed recommender system has an improved performance and it can operate
on embedded consumer devices with limited computational resources.


  Few layer graphene/carbon (FLG/C) composites are prepared directly via the
rapid and simple exfoliation of expanded graphite in the presence of carbon
based natural precursors (i.e. protein, polysaccharide) in water, followed by
carbonization process. Several parameters such as nature of C-precursor, FLG/C
ratio and carbonization conditions (gas, temperature) are modified in order to
optimize the morphology, composition and porosity of FLG/C and thereby
investigate their impact on gravimetric and volumetric capacitance, their
stability and contribution of pseudocapacitance (Ps) vs. double-layer
capacitance (DL). Few composites exhibit extremely high capacitance considering
their low BET-surface area ranging in 130-260 m2/g. The highest gravimetric and
volumetric capacitance of 322 F/g and 467 F/cm3 respectively (0.5 A/g); and
energy/power performance is reached for FLG/C:1/2, synthesized from
graphite-bovine serum albumin(BSA). Despite relatively high theoretical
pseudocapacitance contribution of 69% (1.1V), this sample shows also high
capacity retention at high current density and elevated energy-to-power
densities. The overall great capacity performance is attributed to the high
electrochemical surface area from combined structural features: nanoporosity,
FLG alignment with high accessibility of FLG edges and elevated packing
density.


  The sensitivity of the Statistical Multifragmentation Model to the underlying
statistical assumptions is investigated. We concentrate on its micro-canonical,
canonical, and isobaric formulations. As far as average values are concerned,
our results reveal that all the ensembles make very similar predictions, as
long as the relevant macroscopic variables (such as temperature, excitation
energy and breakup volume) are the same in all statistical ensembles. It also
turns out that the multiplicity dependence of the breakup volume in the
micro-canonical version of the model mimics a system at (approximately)
constant pressure, at least in the plateau region of the caloric curve.
However, in contrast to average values, our results suggest that the
distributions of physical observables are quite sensitive to the statistical
assumptions. This finding may help deciding which hypothesis corresponds to the
best picture for the freeze-out stage


  Systematic variations in the line strength indices H_beta, Mg2, and <Fe> are
observed across elliptical galaxies and from one object to another. Furthermore
arguments are given for an enhancement of Mg (\alfa in general) with respect to
Fe toward the center of these galaxies. In this study we have investigated the
ability of the H_beta, Mg2 and <Fe> diagnostics to assess the metallicity,
[Mg/Fe] ratios, and ages of elliptical galaxies. To this aim, first we derive
basic calibrations for the variations dH_beta, dMg2 and d<Fe> as a function of
Dlog(t), Dlog(Z/Zo), and D[Mg/Fe]. Second, we analyze how the difference
dH_beta, dMg2, and d<Fe> between the external and central values translates
into D[Mg/Fe], Dlog(Z/Zo), and Dlog(t). Third, we explore the variation from
galaxy to galaxy of the nuclear values of H_beta, Mg2, and <Fe> limited to a
sub-sample of the Gonzales (1993) list. The differences dH_beta, dMg2, and
d<Fe> are converted into the differences Dlog(t), Dlog(Z/Zo), and D[Mg/Fe].
Various correlations among the age, metallicity, and enhancement variations are
explored. In particular we thoroughly examine the relationship Dlog(t)-Mv. It
is found that a sort of age limit is likely to exist in this plane, traced by
galaxies with mild or no sign of rejuvenation. In these objects, the duration
of the star forming activity is likely to have increased at decreasing galactic
mass. The results are discussed in the context of current theories of galaxy
formation and evolution. i.e. merger and isolation. Finally, the suggestion is
advanced that models with time and space dependent IMF might be able to
alleviate some of the difficulties encountered by the standard SN-driven
galactic wind model.


  The Infrared Space Observatory (ISO) is used to carry out mid-IR (7 and 15
micron) and far-IR (90 micron) observations of a sample of star-forming sub-mJy
radio sources. By selecting the sample at radio wavelengths, one avoids biases
due to dust obscuration. It is found that the mid-IR luminosities, covering the
PAH features, measure the star formation rate for galaxies with $P_{1.4 GHz} <
10^{23}$ W Hz$^{-1}$. This is further confirmed using the H$\alpha$
luminosities. The far-IR emission is also found to trace the SFR over the whole
range of radio and H$\alpha$ luminosities. The implication of the mid-IR
measurements in estimating the SFRs from the future infrared space missions
(SIRTF and ASTRO-F) is discussed.


  We discuss the role of auxiliary functions in the development of
transcendental number theory.


  Spatially homogeneous random walks in $(\mathbb{Z}_{+})^{2}$ with non-zero
jump probabilities at distance at most 1, with non-zero drift in the interior
of the quadrant and absorbed when reaching the axes are studied. Absorption
probabilities generating functions are obtained and the asymptotic of
absorption probabilities along the axes is made explicit. The asymptotic of the
Green functions is computed along all different infinite paths of states, in
particular along those approaching the axes.


  Hydrogen intercalation in solids is common, complicated, and very difficult
to monitor. In a new approach to the problem, we have studied the profile of
hydrogen diffusion in single-crystal nanobeams and plates of VO2, exploiting
the fact that hydrogen doping in this material leads to visible darkening near
room temperature connected with the metal-insulator transition at 65 {\deg}C.
We observe hydrogen diffusion along the rutile c-axis but not perpendicular to
it, making this a highly one-dimensional diffusion system. We obtain an
activated diffusion coefficient, ~0.01 e^(-0.6 eV/k_B T) cm2sec-1, applicable
in metallic phase. In addition, we observe dramatic supercooling of the
hydrogen-induced metallic phase and spontaneous segregation of the hydrogen
into stripes implying that the diffusion process is highly nonlinear, even in
the absence of defects. Similar complications may occur in hydrogen motion in
other materials but are not revealed by conventional measurement techniques.