title: The SP theory of intelligence: benefits and applications

abstract:
  This article describes existing and expected benefits of the "SP theory of
intelligence", and some potential applications. The theory aims to simplify and
integrate ideas across artificial intelligence, mainstream computing, and human
perception and cognition, with information compression as a unifying theme. It
combines conceptual simplicity with descriptive and explanatory power across
several areas of computing and cognition. In the "SP machine" -- an expression
of the SP theory which is currently realized in the form of a computer model --
there is potential for an overall simplification of computing systems,
including software. The SP theory promises deeper insights and better solutions
in several areas of application including, most notably, unsupervised learning,
natural language processing, autonomous robots, computer vision, intelligent
databases, software engineering, information compression, medical diagnosis and
big data. There is also potential in areas such as the semantic web,
bioinformatics, structuring of documents, the detection of computer viruses,
data fusion, new kinds of computer, and the development of scientific theories.
The theory promises seamless integration of structures and functions within and
between different areas of application. The potential value, worldwide, of
these benefits and applications is at least $190 billion each year. Further
development would be facilitated by the creation of a high-parallel,
open-source version of the SP machine, available to researchers everywhere.


title: Semi-supervised Ranking Pursuit

abstract:
  We propose a novel sparse preference learning/ranking algorithm. Our
algorithm approximates the true utility function by a weighted sum of basis
functions using the squared loss on pairs of data points, and is a
generalization of the kernel matching pursuit method. It can operate both in a
supervised and a semi-supervised setting and allows efficient search for
multiple, near-optimal solutions. Furthermore, we describe the extension of the
algorithm suitable for combined ranking and regression tasks. In our
experiments we demonstrate that the proposed algorithm outperforms several
state-of-the-art learning methods when taking into account unlabeled data and
performs comparably in a supervised learning scenario, while providing sparser
solutions.


title:
Doubling the Critical Current Density of High Temperature
  Superconducting Coated Conductors through Proton Irradiation

abstract:
  The in-field critical current of commercial YBa2Cu3O7 coated conductors can
be substantially enhanced by post-fabrication irradiation with 4 MeV protons.
Irradiation to a fluence of 8x10^16 p/cm^2 induces a near doubling of the
critical current in fields of 6 T || c at a temperature of 27 K, a field and
temperature range of interest for applications such as rotating machinery. A
mixed pinning landscape of preexisting precipitates and twin boundaries and
small, finely dispersed irradiation induced defects may account for the
improved vortex pinning in high magnetic fields. Our data indicate that there
is significant head-room for further enhancements.


title:
A generalization of the Cai--Galloway splitting theorem to smooth metric
  measure spaces

abstract:
  We generalize the splitting theorem of Cai-Galloway for complete Riemannian
manifolds with $\Ric\geq-(n-1)$ admitting a family of compact hypersurfaces
tending to infinity with mean curvatures tending to $n-1$ sufficiently fast to
the setting of smooth metric measure spaces. This result complements and
provides a new perspective on the splitting theorems recently proven by
Munteanu-Wang and Su-Zhang. We show that the mean curvature assumption in our
result is sharp, which also provides an example showing that the assumption
$R\geq-(n-1)$ in the Munteanu-Wang splitting theorem for expanding gradient
Ricci solitons cannot be relaxed to $R>-n$. We also use our result to study a
certain class of conformally compact quasi-Einstein metrics, giving, as
generalizations of respective results of Cai-Galloway and Lee, necessary
conditions for the boundary to be connected and for the bottom of the spectrum
of the weighted Laplacian to be maximal.


title: Single Video Performance Analysis for Video-on-Demand Systems

abstract:
  We study the content placement problem for cache delivery video-on-demand
systems under static random network topologies with fixed heavy-tailed video
demand. The performance measure is the amount of server load; we wish to
minimize the total download rate for all users from the server and maximize the
rate from caches. Our approach reduces the analysis for multiple videos to
consideration of decoupled systems with a single video each. For each placement
policy, insights gained from the single video analysis carry back to the
original multiple video content placement problem. Finally, we propose a hybrid
placement technique that achieves near optimal performance with low complexity.


title: A Porous, Layered Heliopause

abstract:
  The picture of the heliopause (HP) -- the boundary between the domains of the
sun and the local interstellar medium (LISM) -- as a pristine interface with a
large rotation in the magnetic field fails to describe recent Voyager 1 (V1)
spacecraft data. Magnetohydrodynamic (MHD) simulations of the global
heliosphere reveal that the rotation angle of the magnetic field across the HP
at V1 is small. Particle-in-cell simulations, based on cuts through the MHD
model at the location of V1, suggest that the sectored region of the
heliosheath (HS) produces large-scale magnetic islands that reconnect with the
interstellar magnetic field and mix LISM and HS plasma. Cuts across the
simulation data reveal multiple, anti-correlated jumps in the number densities
of LISM and HS particles at the magnetic separatrices of the islands, similar
to those observed by V1. A model is presented, based on both the observations
and simulation data, of the HP as a porous, multi-layered structure threaded by
magnetic fields. This model further suggests that, contrary to the conclusions
of recent papers, V1 has already crossed the HP.


title: The NMSSM at the Cosmic Frontier for Snowmass 2013

abstract:
  We examine the NMSSM at the cosmic frontier in the post Higgs discovery
world. For DM relic abundance consistent with measurement, we find the
neutralino can either be singlino or bino dominated. Wino and higgsino DM
generally yield a lower abundance, but offer opportunities of detection at
IceCube. For both cases, future SI direct detection experiments cover a
majority of the model, including nearly all of the bino and higgsino scenarios.


title:
Directed-polymer systems explored via their quantum analogs: General
  polymer interactions and their consequences

abstract:
  The impact of polymer-polymer interactions of various types on the
thermodynamics, structure, and accommodation of topological constraints is
addressed for systems comprising many directed polymers in two spatial
dimensions. The approach is predicated on the well-known equivalence between
the classical equilibrium statistical mechanics of directed polymers in two
spatial dimensions and the imaginary-time quantum dynamics of particles in one
spatial dimension, originally exploited by P.-G. de Gennes [J.\ Chem.\ Phys.\
{\bf 48}, 2257 (1968)]. Known results concerning two exactly solvable
microscopic models of quantum particles moving in one spatial dimension---the
Lieb-Liniger model of contact interactions and the Calogero-Sutherland model of
long-range interactions---are used to shed light on the behavior of the
corresponding polymeric systems. In addition, the technique of bosonization is
used to reveal how generic polymer interactions give rise to an emergent
polymer fluid that has universal collective excitations. Comparison of the
response to topological constraints of a fluid of simply noncrossing (i.e.,
noncrossing but otherwise noninteracting) directed polymers, explored in a
companion Paper, to the response of a generically interacting directed polymer
fluid reveals that the structure is quantitatively unchanged by the generic
interactions on the line transverse to the pin, and is qualitatively unchanged
by the generic interactions throughout the two dimensions of the system's
extent. Furthermore, the free-energy cost associated with a pin that partitions
a system having generic interactions is found to be proportional to the
pin-partitioning cost for a system of simply noncrossing polymers.


title:
Reversal mode instability and magnetoresistance in perpendicular
  (Co/Pd)/Cu/(Co/Ni) pseudo-spin-valves

abstract:
  We have observed distinct temperature-dependent magnetization reversal modes
in a perpendicular (Co/Pd)4/Co/Cu/(Co/Ni)4/Co pseudo-spin-valve, which are
correlated with spin-transport properties. At 300 K, magnetization reversal
occurs by vertically correlated domains. Below 200 K the hysteresis loop
becomes bifurcated due to laterally correlated reversal of the individual
stacks. The magnetic configuration change also leads to higher spin disorders
and a significant increase in the giant magnetoresistance effect. First order
reversal curve measurements reveal that the coupled state can be re-established
through field cycling, and allow direct determination of the interlayer
coupling strength as a function of temperature.


title: Constraining the location of rapid gamma-ray flares in the FSRQ 3C 273

abstract:
  We present a \gamma-ray photon flux and spectral variability study of the
flat-spectrum radio quasar 3C 273 over a rapid flaring activity period between
September 2009 to April 2010. Five major flares are observed in the source
during this period. The most rapid flare observed in the source has a flux
doubling time of 1.1 hr. The rapid \gamma-ray flares allow us to constrain the
location and size of the \gamma-ray emission region in the source. The \gamma
\gamma-opacity constrains the Doppler factor, $\delta_{\gamma} \geq$ 10 for the
highest energy (15 GeV) photon observed by the {\it Fermi}-Large Area Telescope
(LAT). Causality arguments constrain the size of the emission region to
1.6$\times 10^{15}$ cm. The \gamma-ray spectra measured over this period show
clear deviations from a simple power law with a break in 1-2 GeV energy range.
We discuss possible explanations for the origin of the \gamma-ray spectral
breaks. Our study suggests that the \gamma-ray emission region in 3C 273 is
located within the broad line region ($<$1.6 pc). The spectral behavior and
temporal characteristics of the individual flares indicate the presence of
multiple shock scenarios at the base of the jet.


title: A Local Control Approach to Voltage Regulation in Distribution Networks

abstract:
  This paper address the problem of voltage regulation in power distribution
networks with deep penetration of distributed energy resources (DERs) without
any explicit communication between the buses in the network. We cast the
problem as an optimization problem with the objective of minimizing the
distance between the bus voltage magnitudes and some reference voltage profile.
We present an iterative algorithm where each bus updates the reactive power
injection provided by their DER. The update at a bus only depends on the
voltage magnitude at that bus, and for this reason, we call the algorithm a
local control algorithm. We provide sufficient conditions that guarantee the
convergence of the algorithm and these conditions can be checked a priori for a
set of feasible power injections. We also provide necessary conditions
establishing that longer and more heavily loaded networks are inherently more
difficult to control. We illustrate the operation of the algorithm through case
studies involving 8-,34- and 123-bus test distribution systems.


title:
The Relative Role of Galaxy Mergers and Cosmic Flows in Feeding Black
  Holes

abstract:
  Using a set of zoomed-in cosmological simulations of high-redshift
progenitors of massive galaxies, we isolate and trace the history of gas that
is accreted by central supermassive black holes. We determine the origins of
the accreted gas, in terms of whether it entered the galaxy during a merger
event or was smoothly accreted. Furthermore, we designate whether the smoothly
accreted gas is accreted via a cold flow or is shocked upon entry into the
halo. For moderate-mass (10^6 - 10^7 Msun) black holes at z ~ 4, there is a
preference to accrete cold flow gas than gas of shocked or merger origin.
However, this result is a consequence of the fact that the entire galaxy has a
higher fraction of gas from cold flows. In general, each black hole tends to
accrete the same fractions of smooth- and merger-accreted gas as is contained
in its host galaxy, suggesting that once gas enters a halo it becomes
well-mixed, and its origins are erased. We find that the angular momentum of
the gas upon halo entry is a more important factor; black holes preferentially
accrete gas that had low angular momentum when it entered the galaxy,
regardless of whether it was accreted smoothly or through mergers.


title: Characterization of Boolean Networks with Single or Bistable States

abstract:
  Many biological systems, such as metabolic pathways, exhibit bistability
behavior: these biological systems exhibit two distinct stable states with
switching between the two stable states controlled by certain conditions. Since
understanding bistability is key for understanding these biological systems,
mathematical modeling of the bistability phenomenon has been at the focus of
researches in quantitative and system biology. Recent study shows that Boolean
networks offer relative simple mathematical models that are capable of
capturing these essential information. Thus a better understanding of the
Boolean networks with bistability property is desirable for both theoretical
and application purposes. In this paper, we describe an algebraic condition for
the number of stable states (fixed points) of a Boolean network based on its
polynomial representation, and derive algorithms for a Boolean network to have
a single stable state or two stable states. As an example, we also construct a
Boolean network with exactly two stable states for the lac operon's
$\beta$-galactosidase regulatory pathway when glucose is absent based on a
delay differential equation model


title: Error models in quantum computation: an application of model selection

abstract:
  Threshold theorems for fault-tolerant quantum computing assume that errors
are of certain types. But how would one detect whether errors of the "wrong"
type occur in one's experiment, especially if one does not even know what type
of error to look for? The problem is that for many qubits a full state
description is impossible to analyze, and a full process description is even
more impossible to analyze. As a result, one simply cannot detect all types of
errors. Here we show through a quantum state estimation example (on up to 25
qubits) how to attack this problem using model selection. We use, in
particular, the Akaike Information Criterion. The example indicates that the
number of measurements that one has to perform before noticing errors of the
wrong type scales polynomially both with the number of qubits and with the
error size.


title: Dynamics on the PSL(2,C)-character variety of a compression body

abstract:
  Let M be a nontrivial compression body without toroidal boundary components.
We study the dynamics of the group of outer automorphisms of the fundamental
group of M on the PSL(2,C)-character variety of M.


abstract:
  We study the relation between the vanishing of Andr\'{e}-Quillen homology and
complete intersection flat dimension and we extend some of the existing results
in the literature.


title:
Reconstruction of Signals Drawn from a Gaussian Mixture from Noisy
  Compressive Measurements

abstract:
  This paper determines to within a single measurement the minimum number of
measurements required to successfully reconstruct a signal drawn from a
Gaussian mixture model in the low-noise regime. The method is to develop upper
and lower bounds that are a function of the maximum dimension of the linear
subspaces spanned by the Gaussian mixture components. The method not only
reveals the existence or absence of a minimum mean-squared error (MMSE) error
floor (phase transition) but also provides insight into the MMSE decay via
multivariate generalizations of the MMSE dimension and the MMSE power offset,
which are a function of the interaction between the geometrical properties of
the kernel and the Gaussian mixture. These results apply not only to standard
linear random Gaussian measurements but also to linear kernels that minimize
the MMSE. It is shown that optimal kernels do not change the number of
measurements associated with the MMSE phase transition, rather they affect the
sensed power required to achieve a target MMSE in the low-noise regime.
Overall, our bounds are tighter and sharper than standard bounds on the minimum
number of measurements needed to recover sparse signals associated with a union
of subspaces model, as they are not asymptotic in the signal dimension or
signal sparsity.


title: Ising model on directed small-world Voronoi Delaunay random lattices

abstract:
  We investigate the critical properties of the Ising model in two dimensions
on {\it directed} small-world lattice with quenched connectivity disorder. The
disordered system is simulated by applying the Monte Carlo update heat bath
algorithm. We calculate the critical temperature, as well as the critical
exponents $\gamma/\nu$, $\beta/\nu$, and $1/\nu$ for several values of the
rewiring probability $p$. We find that this disorder system does not belong to
the same universality class as the regular two-dimensional ferromagnetic model.
The Ising model on {\it directed} small-world lattices presents in fact a
second-order phase transition with new critical exponents which do not
dependent of $p$, but are identical to the exponents of the Ising model and the
spin-1 Blume-Capel model on {\it directed} small-world network.


title: Abelian surfaces over finite fields with prescribed groups

abstract:
  Let A be an abelian surface over F_q, the field of q elements. The rational
points on A/\F_q form an abelian group A(\F_q) \simeq \Z/n_1\Z \times \Z/n_1
n_2 \Z \times \Z/n_1 n_2 n_3\Z \times\Z/n_1 n_2 n_3 n_4\Z. We are interested in
knowing which groups of this shape actually arise as the group of points on
some abelian surface over some finite field. For a fixed prime power q, a
characterization of the abelian groups that occur was recently found by
Rybakov. One can use this characterization to obtain a set of congruences
modulo the integers $n_1, n_2, n_3, n_4$ on certain combinations of
coefficients of the corresponding Weil polynomials. We use Rybakov's criterion
to show that groups \Z/n_1\Z \times \Z/n_1 n_2 \Z \times \Z/n_1 n_2 n_3\Z
\times\Z/n_1 n_2 n_3 n_4\Z do not occur if n_1 is very large with respect to
n_2, n_2, n_4 (Theorem \ref{splitbound}), and occur with density zero in a
wider range of the variables (Theorem \ref{splitbound-average}).


title:
Comparison of magnetic field uniformities for discretized and
  finite-sized standard $\cos\theta$, solenoidal, and spherical coils

abstract:
  A significant challenge for experiments requiring a highly uniform magnetic
field concerns the identification and design of a discretized and finite-sized
magnetic field coil of minimal size. In this work we compare calculations of
the magnetic field uniformities and field gradients for three different
standard (i.e., non-optimized) types of coils: $\cos\theta$, solenoidal, and
spherical coils. For an experiment with a particular requirement on either the
field uniformity or the field gradient, we show that the volume required by a
spherical coil form which satisfies these requirements can be significantly
less than the volumes required by $\cos\theta$ and solenoidal coil forms.


title:
Direct Imaging of a Compact Molecular Outflow from a Very Low-luminosity
  Object; L1521F-IRS

abstract:
  We report interferometric observations of the VeLLO L1521F-IRS, in 12CO (2-1)
line emission and the 1.3 mm continuum emission, using the Submillimeter Array
(SMA). With the 12CO high-resolution observations, we have spatially resolved a
compact but poorly collimated molecular outflow associated with L1521F-IRS for
the first time. The blueshifted and redshifted lobes are aligned along the east
and west side of L1521F-IRS with a lobe size of ~1000 AU. The estimated outflow
mass, maximum outflow velocity, and outflow force are (9.0-80)x10^{-4} M_{sol},
7.2 km s^{-1}, and (7.4-66)x10^{-7} M_{sol} km s^{-1} yr^{-1}, respectively.
The estimated outflow parameters such as size, mass, and momentum rate are
similar to values derived for other VeLLOs, and are located at the lower end of
values compared to previously studied outflows associated with low- to
high-mass star forming regions. Low-velocity less collimated (1.5 km
s^{-1}/1200 AU) and higher-velocity compact (4.0 km s^{-1}/920 AU) outflow
components are suggested by the data. These velocity structures are not
consistent with those expected in the jet driven or wind driven outflow models,
perhaps suggesting a remnant outflow from the FHSC as well as an undeveloped
outflow from the protostar. Detection of an infrared source and compact
millimeter continuum emission suggest the presence of the protostar, while its
low bolometric luminosity (0.034-0.07 L$_{\odot}$), and small outflow, suggests
that L1521F is in the earliest protostellar stage ($<10^{4}$ yr) and contains a
substellar mass object. The bolometric (or internal) luminosity of L1521F-IRS
suggests that the current mass accretion rate is an order-of-magnitude lower
than expected in the standard mass accretion model (~10^{-6} M_{sol} yr^{-1}),
which may imply that L1521F-IRS is currently in a low activity phase.


title: Overlap Technique for End-Cap Seals on Cylindrical Magnetic Shields

abstract:
  We present results from studies of the effectiveness of an overlap technique
for forming a magnetic seal across a gap at the boundary between a cylindrical
magnetic shield and an end-cap. In this technique a thin foil of magnetic
material overlaps the two surfaces, thereby spanning the gap across the
cylinder and the end-cap, with the magnetic seal then formed by clamping the
thin magnetic foil to the surfaces of the cylindrical shield and the end-cap on
both sides of the gap. In studies with a prototype 31-cm diameter, 91-cm long,
0.16-cm thick cylindrical magnetic shield and flared end-cap, the magnetic
shielding performance of our overlap technique is comparable to that obtained
with the conventional method in which the end-cap is placed in direct lapped
contact with the cylindrical shield via through bolts or screws.


title: On the theorem of Conrey and Iwaniec

abstract:
  An exposition on "Spacing of zeros of Hecke L-functions and the class number
problem" by Conrey and Iwaniec; any errors are my own.


title:
The strain gap in a system of weakly and strongly interacting two-level
  systems

abstract:
  Many disordered lattices exhibit remarkable universality in their low
temperature properties, similar to that found in amorphous solids. Recently a
two-TLS (two-level system) model was derived based on the microscopic
characteristics of disordered lattices. Within the two-TLS model the
quantitative universality of phonon attenuation, and the energy scale of $1-3$
K below which universality is observed, are derived as a consequence of the
existence of two types of TLSs, differing by their interaction with the phonon
field. In this paper we calculate analytically and numerically the densities of
states (DOS) of the weakly and strongly interacting TLSs. We find that the DOS
of the former can be well described by a Gaussian, whereas the DOS of the
latter have a power law correlation gap at low energies, with an intriguing
dependence of the power on the short distance cutoff of the interaction. Both
behaviors are markedly different from the logarithmic gap exhibited by a single
species of interacting TLSs. Our analytical results are verified against
extensive Monte Carlo simulations. Our results support the notion that it is
the weakly interacting $\tau$-TLSs that dictate the standard low temperature
glassy physics. Yet, the power-law DOS we find for the $S$-TLSs enables the
prediction of a number of deviations from the universal glassy behavior that
can be tested experimentally. Possible relevance of our results to recent
experimental findings in hydrogenated amorphous films, and more generally to
amorphous systems, is discussed.


title:
Systematic identification of gene families for use as markers for
  phylogenetic and phylogeny- driven ecological studies of bacteria and archaea
  and their major subgroups

abstract:
  With the astonishing rate that the genomic and metagenomic sequence data sets
are accumulating, there are many reasons to constrain the data analyses. One
approach to such constrained analyses is to focus on select subsets of gene
families that are particularly well suited for the tasks at hand. Such gene
families have generally been referred to as marker genes. We are particularly
interested in identifying and using such marker genes for phylogenetic and
phylogeny-driven ecological studies of microbes and their communities. We
therefore refer to these as PhyEco (for phylogenetic and phylogenetic ecology)
markers. The dual use of these PhyEco markers means that we needed to develop
and apply a set of somewhat novel criteria for identification of the best
candidates for such markers. The criteria we focused on included universality
across the taxa of interest, ability to be used to produce robust phylogenetic
trees that reflect as much as possible the evolution of the species from which
the genes come, and low variation in copy number across taxa. We describe here
an automated protocol for identifying potential PhyEco markers from a set of
complete genome sequences. The protocol combines rapid searching, clustering
and phylogenetic tree building algorithms to generate protein families that
meet the criteria listed above. We report here the identification of PhyEco
markers for different taxonomic levels including 40 for all bacteria and
archaea, 114 for all bacteria, and much more for some of the individual phyla
of bacteria. This new list of PhyEco markers should allow much more detailed
automated phylogenetic and phylogenetic ecology analyses of these groups than
possible previously.


title: Distinct Distances on Curves via Rigidity

abstract:
  It is shown that $N$ points on a real algebraic curve of degree $n$ in
$\mathbb{R}^d$ always determine $\gtrsim_{n,d}N^{1+\frac{1}{4}}$ distinct
distances, unless the curve is a straight line or the closed geodesic of a flat
torus. In the latter case, there are arrangements of $N$ points which determine
$\lesssim N$ distinct distances. The method may be applied to other quantities
of interest to obtain analogous exponent gaps. An important step in the proof
involves understanding the structural rigidity of certain frameworks on curves.


title:
Matrix Characterization of Knots: A Simple Statistical Mechanics
  Application

abstract:
  In this note, I describe a formalism for treating knots as geometric spaces,
and make an application to a simple statistical mechanics computation. The
motivation for this study is the natural visual symmetry of the knot, and I
describe how this might be carried out. The direct approach, however, fails due
to limits of the visual symmetry, but by recasting the problem in terms of the
geometry of contours of the knot, the resulting permutation operators provide a
better analytical tool.


title: Maximization of recursive utilities under convex portfolio constraints

abstract:
  We study a robust maximization problem from terminal wealth and consumption
under a convex constraints on the portfolio. We state the existence and the
uniqueness of the consumption-investment strategy by studying the associated
quadratic backward stochastic differential equation (BSDE in short). We
characterize the optimal control by using the duality method and deriving a
dynamic maximum principle.


title: New Analysis and Results for the Frank-Wolfe Method

abstract:
  We present new results for the Frank-Wolfe method (also known as the
conditional gradient method). We derive computational guarantees for arbitrary
step-size sequences, which are then applied to various step-size rules,
including simple averaging and constant step-sizes. We also develop step-size
rules and computational guarantees that depend naturally on the warm-start
quality of the initial (and subsequent) iterates. Our results include
computational guarantees for both duality/bound gaps and the so-called FW gaps.
Lastly, we present complexity bounds in the presence of approximate computation
of gradients and/or linear optimization subproblem solutions.


title: Solution of the minimum modulus problem for covering systems

abstract:
  We answer a question of Erd\H{o}s by showing that the least modulus of a
distinct covering system of congruences is no larger than $10^{18}$.


title:
The obstacle problem for semilinear parabolic partial
  integro-differential equations

abstract:
  This paper presents a probabilistic interpretation for the weak Sobolev
solution of the obstacle problem for semilinear parabolic partial
integro-differential equations (PIDEs).
  The results of Leandre (1985) concerning the homeomorphic property for the
solution of SDEs with jumps are used to construct random test functions for the
variational equation for such PIDEs. This results in the natural connection
with the associated Reflected Backward Stochastic Differential Equations with
jumps (RBSDEs), namely Feynman Kac's formula for the solution of the PIDEs.
Moreover it gives an application to the pricing and hedging of contingent
claims with constraints in the wealth or portfolio processes in financial
markets including jumps.


title: An MsFEM type approach for perforated domains

abstract:
  We follow up on our previous work [C. Le Bris, F. Legoll and A. Lozinski,
Chinese Annals of Mathematics 2013] where we have studied a multiscale finite
element (MsFEM) type method in the vein of the classical Crouzeix-Raviart
finite element method that is specifically adapted for highly oscillatory
elliptic problems. We adapt the approach to address here a multiscale problem
on a perforated domain. An additional ingredient of our approach is the
enrichment of the multiscale finite element space using bubble functions. We
first establish a theoretical error estimate. We next show that, on the problem
we consider, the approach we propose outperforms all dedicated existing
variants of MsFEM we are aware of.


title:
Uniqueness for the inverse backscattering problem for angularly
  controlled potentials

abstract:
  We consider the problem of recovering a smooth, compactly supported potential
on R^3 from its backscattering data. We show that if two such potentials have
the same backscattering data and the difference of the two potentials has
controlled angular derivatives then the two potentials are identical. In
particular, if two potentials differ by a finite linear combination of
spherical harmonics with radial coefficinets and have the same backscattering
data then the two potentials are identical.


title:
Stable long-distance propagation and on-off switching of colliding
  soliton sequences with dissipative interaction

abstract:
  We study propagation and on-off switching of two colliding soliton sequences
in the presence of second-order dispersion, Kerr nonlinearity, linear loss,
cubic gain, and quintic loss. Employing a Lotka-Volterra (LV) model for
dynamics of soliton amplitudes along with simulations with two perturbed
coupled nonlinear Schr\"odinger (NLS) equations, we show that stable
long-distance propagation can be achieved for a wide range of the gain-loss
coefficients, including values that are outside of the perturbative regime.
Furthermore, we demonstrate robust on-off and off-on switching of one of the
sequences by an abrupt change in the ratio of cubic gain and quintic loss
coefficients, and extend the results to pulse sequences with periodically
alternating phases. Our study significantly strengthens the recently found
relation between collision dynamics of sequences of NLS solitons and population
dynamics in LV models, and indicates that the relation might be further
extended to solitary waves of the cubic-quintic Ginzburg-Landau equation.


title: Cohen-Lenstra heuristics and random matrix theory over finite fields

abstract:
  Let g be a random element of a finite classical group G, and let
\lambda_{z-1}(g) denote the partition corresponding to the polynomial z-1 in
the rational canonical form of g. As the rank of G tends to infinity,
\lambda_{z-1}(g) tends to a partition distributed according to a Cohen-Lenstra
type measure on partitions. We give sharp upper and lower bounds on the total
variation distance between the random partition \lambda_{z-1}(g) and the
Cohen-Lenstra type measure.


title:
Modelling and simulation of acrylic bone cement injection and curing
  within the framework of vertebroplasty

abstract:
  The minimal invasive procedure of vertebroplasty is a surgical technique to
treat compression fractures of vertebral bodies. During the treatment, liquid
bone cement gets injected into the affected vertebral body and therein cures to
a solid. In order to investigate the treatment and the impact of injected bone
cement, an integrated modelling and simulation framework has been developed.
The framework includes (i) the generation of microstructural computer models
based on microCT images of human cancellous bone, (ii) computational fluid
dynamics (CFD) simulations of bone cement injection into the trabecular
structure and (iii) non-linear finite element (FE) simulations of the
subsequent bone cement curing. A detailed description of the material behaviour
of acrylic bone cements is provide d for both simulation stages. A non-linear
process-depending fluid flow model is chosen to represent the bone cement
behaviour during injection. The bone cements phase change from a highly viscous
fluid to a solid is described by a non-linear viscoelastic material model with
curing dependent properties. To take into account the distinctive temperature
dependence of acrylic bone cements, both material models are formulated in a
thermo-mechanically coupled manner. Moreover, the corresponding microstructural
CFD- and FE-simulations are performed using thermo-mechanically coupled
solvers. An application of the presented modelling and simulation framework to
a sample of human cancellous bone demonstrates the capabilities of the
presented approach.


title: Optical and Near-Infrared Shocks in the L988 Cloud Complex

abstract:
  We have searched the Lynds 988 dark cloud complex for optical (\ha{} and
\sii{}) and near-IR (\mh{} 2.12 $\mu$m) shocks from protostellar outflows. We
find 20 new Herbig-Haro objects and 6 new \mh{} shocks (MHO objects), 3 of
which are cross detections. Using the morphology in the optical and near-IR, we
connect several of these shocks into at least 5 distinct outflow systems and
identify their source protostars from catalogs of infrared sources.
  Two outflows in the cloud, from IRAS 21014+5001 and IRAS 21007+4951, are in
excess of 1 pc in length. The IRAS 21007+4951 outflow has carved a large cavity
in the cloud through which background stars can be seen. Also, we have found an
optical shock which is the counterflow to the previously discovered "northwest
outflow" from LkHa 324SE.


title: Small-time Sampling Behaviour of a Fleming-Viot Process

abstract:
  The Fleming-Viot process with parent-independent mutation process is one
particular neutral population genetic model. As time goes by, some initial
species are replaced by mutated ones gradually. Once the population mutation
rate is high, mutated species will elbow out all the initial species very
quickly. Small time behaviour in this case seems to be the key to understand
this fast transition. The small-time asymptotic results related to time scale
$\frac{t}{\theta}$ and $a(\theta)t$, where $\lim_{\theta\to\infty}\theta
a(\theta)=0$, are obtained in \cite{MR1815182},\cite{MR1649005},
\cite{MR1887170} and \cite{MR2184086}, respectively. Only the behaviour under
the scale $t(\theta)$, where $\lim_{\theta\to\infty}\theta a(\theta)=\infty$,
was left untouched. In this paper, the weak limits under various small time
scales are obtained. Of particular interest is the large deviations for the
small-time transient sampling distributions, which reveal interesting phase
transition. Interestingly, such a phase transition is uniquely determined by
some species diversity indices.


title: Ergodic Inequality of Three Population Genetic Models

abstract:
  In this article, three models are considered, they are the
infinitely-many-neutral-alleles model \cite{MR615945}, infinite dimensional
diffusion associated with two-parameter Poisson-Dirichlet distribution
\cite{MR2596654} and the infinitely-many-alleles model with symmetric dominance
\cite{MR1626158}. The new representations of the transition transition
densities are obtained for the first two models. Lastly, the ergodic
inequalities of these three models are provided.


title: Probing Lorentz Invariance Violation with Neutrino Factories

abstract:
  In this article we show the modification in the number of neutrino events
($\nu_\mu+\bar\nu_\mu$) caused by Lorentz Invariant Violation (LIV),
$\sigma=5\times 10^{-24}$ and $10^{-23}$, in neutrino oscillation for a
neutrino factory at a distance of 7500 km. The momentum of the muons can vary
from 10-50 GeV and we consider $2\times 10^{20}$ decays per year. The
modifications in the number of events caused by this $\sigma$ LIV parameter
could be a strong signal of new physics in a future neutrino factory.


title: The Proof of Lin's Conjecture via the Decimation-Hadamard Transform

abstract:
  In 1998, Lin presented a conjecture on a class of ternary sequences with
ideal 2-level autocorrelation in his Ph.D thesis. Those sequences have a very
simple structure, i.e., their trace representation has two trace monomial
terms. In this paper, we present a proof for the conjecture. The mathematical
tools employed are the second-order multiplexing decimation-Hadamard transform,
Stickelberger's theorem, the Teichm\"{u}ller character, and combinatorial
techniques for enumerating the Hamming weights of ternary numbers. As a
by-product, we also prove that the Lin conjectured ternary sequences are
Hadamard equivalent to ternary $m$-sequences.


title:
Atomistic study of energy funneling in the light-harvesting complex of
  green sulfur bacteria

abstract:
  Phototrophic organisms such as plants, photosynthetic bacteria and algae use
microscopic complexes of pigment molecules to absorb sunlight. Within the
light-harvesting complexes, which frequently have several functional and
structural subunits, the energy is transferred in the form of molecular
excitations with very high efficiency. Green sulfur bacteria are considered to
be amongst the most efficient light-harvesting organisms. Despite multiple
experimental and theoretical studies of these bacteria the physical origin of
the efficient and robust energy transfer in their light-harvesting complexes is
not well understood. To study excitation dynamics at the systems level we
introduce an atomistic model that mimics a complete light-harvesting apparatus
of green sulfur bacteria. The model contains approximately 4000 pigment
molecules and comprises a double wall roll for the chlorosome, a baseplate and
six Fenna-Matthews-Olson trimer complexes. We show that the fast relaxation
within functional subunits combined with the transfer between collective
excited states of pigments can result in robust energy funneling. Energy
transfer is robust on the initial excitation conditions and temperature
changes. Moreover, the same mechanism describes the coexistence of multiple
timescales of excitation dynamics frequently observed in ultrafast optical
experiments. While our findings support the hypothesis of supertransfer, the
model reveals energy transport through multiple channels on different length
scales.


title:
Algebraic zeros divisors on the projective line having small diagonals
  and small heights and their application to adelic dynamics

abstract:
  We establish a quantitative adelic equidistribution theorem for a sequence of
algebraic zeros divisors on the projective line over the separable closure of a
product formula field having small diagonals and small $g$-heights with respect
to an adelic normalized weight $g$ in arbitrary characteristic and in possibly
non-separable setting, and obtain local proximity estimates between the
iterations of a rational function $f\in k(z)$ of degree $>1$ and a rational
function $a\in k(z)$ of degree $>0$ over a product formula field $k$ of
characteristic $0$, applying this quantitative adelic equidistribution result
to adelic dynamics of $f$.


title: Numerical Approximation of Fractional Powers of Elliptic Operators

abstract:
  We present and study a novel numerical algorithm to approximate the action of
$T^\beta:=L^{-\beta}$ where $L$ is a symmetric and positive definite unbounded
operator on a Hilbert space $H_0$. The numerical method is based on a
representation formula for $T^{-\beta}$ in terms of Bochner integrals involving
$(I+t^2L)^{-1}$ for $t\in(0,\infty)$.
  To develop an approximation to $T^\beta$, we introduce a finite element
approximation $L_h$ to $L$ and base our approximation to $T^\beta$ on
$T_h^\beta:= L_h^{-\beta}$. The direct evaluation of $T_h^{\beta}$ is extremely
expensive as it involves expansion in the basis of eigenfunctions for $L_h$.
The above mentioned representation formula holds for $T_h^{-\beta}$ and we
propose three quadrature approximations denoted generically by $Q_h^\beta$. The
two results of this paper bound the errors in the $H_0$ inner product of
$T^\beta-T_h^\beta\pi_h$ and $T_h^\beta-Q_h^\beta$ where $\pi_h$ is the $H_0$
orthogonal projection into the finite element space. We note that the
evaluation of $Q_h^\beta$ involves application of $(I+(t_i)^2L_h)^{-1}$ with
$t_i$ being either a quadrature point or its inverse. Efficient solution
algorithms for these problems are available and the problems at different
quadrature points can be straightforwardly solved in parallel. Numerical
experiments illustrating the theoretical estimates are provided for both the
quadrature error $T_h^\beta-Q_h^\beta$ and the finite element error
$T^\beta-T_h^\beta\pi_h$.


title: Sum-free cyclic multi-bases and constructions of Ramsey algebras

abstract:
  Given $X\subseteq \mathbb{Z}_N$, $X$ is called a \emph{cyclic basis} if
$(X+X)\cup X=\mathbb{Z}_N$, \emph{symmetric} if $x\in X$ implies $-x \in X$,
and \emph{sum-free} if $(X+X)\cap X=\varnothing$. We ask, for which $m$,
$N\in\mathbb{Z}^+$ can the set of non-identity elements of $\mathbb{Z}_N$ be
partitioned into $m$ symmetric sum-free cyclic bases? If, in addition, we
require that distinct cyclic bases interact in a certain way, we get a proper
relation algebra called a Ramsey algebra. Ramsey algebras (which have also been
called Monk algebras) have been constructed previously for $2\leq m\leq 7$. In
this manuscript, we provide constructions of Ramsey algebras for every positive
integer $m$ with $2\leq m\leq 400$, with the exception of $m=8$ and $m=13$.


title:
Metal hydride material requirements for automotive hydrogen storage
  systems

abstract:
  The United States Department of Energy (DOE) has published a progression of
technical targets to be satisfied by on-board rechargeable hydrogen storage
systems in light-duty vehicles. By combining simplified storage system and
vehicle models with interpolated data from metal hydride databases, we obtain
material-level requirements for metal hydrides that can be assembled into
systems that satisfy the DOE targets for 2017. We assume minimal
balance-of-plant components for systems with and without a hydrogen combustion
loop for supplemental heating. Tank weight and volume are driven by the
stringent requirements for refueling time. The resulting requirements suggest
that, at least for this specific application, no current on-board rechargeable
metal hydride satisfies these requirements.


title:
Multi-path multi-component self-accelerating beams through
  spectrum-engineered position mapping

abstract:
  We introduce the concept of spatial spectral phase gradient, and demonstrate,
both theoretically and experimentally, how this concept could be employed for
generating single- and multi-path self-accelerating beams. In particular, we
show that the trajectories of the accelerating beams are determined a priori by
different key spatial frequencies through direct spectrum-to-distance mapping.
In the non-paraxial regime, our results clearly illustrate the breakup of Airy
beams from a different perspective, and demonstrate how circular, elliptic or
hyperbolic accelerating beams can be created by judiciously engineering the
spectral phase. Furthermore, we found that the accelerating beams still follow
the predicted trajectory also for vectorial wavefronts. Our approach not only
generalizes the idea of Fourier-space beam engineering along arbitrary convex
trajectories, but also offers new possibilities for beam/pulse manipulation not
achievable through standard direct real-space approaches or by way of
time-domain phase modulation.


title:
Leaky mode analysis of luminescent thin films: the case of ZnO on
  sapphire

abstract:
  Zinc oxide (ZnO) epitaxial thin films grown on c-sapphire substrates by
pulsed laser deposition were investigated using angle and polarization-resolved
photoluminescence spectroscopy. Side-emission spectra differed significantly
from surface-emission spectra in exhibiting dominant, narrow,
polarization-resolved peaks. These spectral features were attributed to leaky
substrate modes in the layers. Observations were first verified using
transmission calculations with non-adjustable parameters, which took into
account the dispersion, the anisotropy of the ZnO refractive index and the
dependence on film thickness. Results were consistent with Fabry-Perot-like
interference being the origin of the distinctive ZnO luminescence observed at
grazing incidence angles. A second analysis, based on the source terms method,
was used in order to retrieve the bulk emission properties, including the
wavelength-dependent quantum yield and the emission anisotropy. While ZnO thin
films were considered here, this analysis method can be extended to any
luminescent thin film of similar geometry, demonstrating the potential of leaky
mode analysis for probing passive and active material properties.


title:
Superconducting nanowire single-photon detector with ultralow dark count
  rate using cold optical filters

abstract:
  We report the fabrication of a superconducting nanowire single-photon
detector (SSPD or SNSPD) with an ultralow dark count rate. By introducing
optical band-pass filters at the input of the SSPD and cooling the filters at 3
K, the dark count rate is reduced to less than 1/100 at low bias. An SSPD with
0.1 cps dark count rate and 5.6% system detection efficiency at 1550 nm
wavelength is obtained. We show that a quantum key distribution (QKD) over 300
km of fiber is possible based on a numerical calculation assuming a
differential phase shift QKD protocol implemented with our SSPDs.

categories: cond-mat.supr-con physics.ins-det physics.optics quant-ph


title:
Forever alone? Testing single eccentric planetary systems for multiple
  companions

abstract:
  Determining the orbital eccentricity of an extrasolar planet is critically
important for understanding the system's dynamical environment and history.
However, eccentricity is often poorly determined or entirely mischaracterized
due to poor observational sampling, low signal-to-noise, and/or degeneracies
with other planetary signals. Some systems previously thought to contain a
single, moderate-eccentricity planet have been shown, after further monitoring,
to host two planets on nearly-circular orbits. We investigate published
apparent single-planet systems to see if the available data can be better fit
by two lower-eccentricity planets. We identify nine promising candidate systems
and perform detailed dynamical tests to confirm the stability of the potential
new multiple-planet systems. Finally, we compare the expected orbits of the
single- and double-planet scenarios to better inform future observations of
these interesting systems.


title:
Narrowband Emission in Thomson Sources Operating in the High-Field
  Regime

abstract:
  We present a novel and quite general analysis of the interaction of a
high-field chirped laser pulse and a relativistic electron, in which exquisite
control of the spectral brilliance of the upshifted Thomson-scattered photon is
shown to be possible. Normally, when Thomson scattering occurs at high field
strengths, there is ponderomotive line broadening in the scattered radiation.
This effect makes the bandwidth too large for some applications and reduces the
spectral brilliance. We show that such broadening can be corrected and
eliminated by suitable frequency modulation of the incident laser pulse.
Further, we suggest a practical realization of this compensation idea in terms
of a chirped-beam driven free electron laser oscillator configuration and show
that significant compensation can occur, even with the imperfect matching to be
expected in these conditions.


title:
Bucking Coil Implementation on PMT for Active Cancelling of Magnetic
  Field

abstract:
  Aerogel and water Cerenkov detectors were employed to tag kaons for a lambda
hypernuclear spectroscopic experiment which used the (e,e'K+) reaction in
experimental Hall C at Jefferson Lab (JLab E05-115). Fringe fields from the
kaon spectrometer magnet yielded ~5 Gauss at the photomultiplier tubes (PMT)
for these detectors which could not be easily shielded. As this field results
in a lowered kaon detection efficiency, we implemented a bucking coil on each
photomultiplier tubes to actively cancel this magnetic field, thus maximizing
kaon detection efficiency.


title:
General theory of feedback control of a nuclear spin ensemble in quantum
  dots

abstract:
  We present a microscopic theory of the nonequilibrium nuclear spin dynamics
driven by the electron and/or hole under continuous wave pumping in a quantum
dot. We show the correlated dynamics of the nuclear spin ensemble and the
electron and/or hole under optical excitation as a quantum feedback loop and
investigate the dynamics of the many nuclear spins as a nonlinear collective
motion. This gives rise to three observable effects: (i) hysteresis, (ii)
locking (avoidance) of the pump absorption strength to (from) the natural
resonance, and (iii) suppression (amplification) of the fluctuation of weakly
polarized nuclear spins, leading to prolonged (shortened) electron spin
coherence time. A single nonlinear feedback function as a "measurement" of the
nuclear field operator in the quantum feedback loop is constructed which
determines the different outcomes of the three effects listed above depending
on the feedback being negative or positive. The general theory also helps to
put in perspective the wide range of existing theories on the problem of a
single electron spin in a nuclear spin bath.


title: Entropy of a Zipfian Distributed Lexicon

abstract:
  This article presents the calculation of the entropy of a system with Zipfian
distribution and shows that a communication system tends to present an exponent
value close to one, but still greater than one, so that it might maximize
entropy and hold a feasible lexicon with an increasing size. This result is in
agreement with what is observed in natural languages and with the balance
between the speaker and listener communication efforts. On the other hand, the
entropy of the communicating source is very sensitive to the exponent value as
well as the length of the observable data, making it a poor parameter to
characterize the communication process.


title: Quasi-One-Dimensional Dipolar Quantum Gases

abstract:
  In this letter we consider dipolar quantum gases in a quasi-one-dimensional
tube with dipole moment perpendicular to the tube direction. We deduce the
effective one-dimensional interaction potential and show that this potential is
not purely repulsive, but rather has an attractive part due to high-order
scattering processes through transverse excited states. The attractive part can
induce bound state and cause scattering resonances. This represents the dipole
induced resonance in low-dimension. We work out an unconventional behavior of
low-energy phase shift for this effective potential and show how it evolves
across a resonance. Based on the phase shift, the interaction energy of
spinless bosons is obtained using asymptotic Bethe ansatz. Despite of
long-range nature of dipolar interaction, we find that a behavior similar as
short-range Lieb-Linger gas emerges at the resonance regime.


title: CD-independent subsets in meet-distributive lattices

abstract:
  A subset $X$ of a finite lattice $L$ is CD-independent if the meet of any two
incomparable elements of $X$ equals 0. In 2009, Cz\'edli, Hartmann and Schmidt
proved that any two maximal CD-independent subsets of a finite distributive
lattice have the same number of elements. In this paper, we prove that if $L$
is a finite meet-distributive lattice, then the size of every CD-independent
subset of $L$ is at most the number of atoms of $L$ plus the length of $L$. If,
in addition, there is no three-element antichain of meet-irreducible elements,
then we give a recursive description of maximal CD-independent subsets.
Finally, to give an application of CD-independent subsets, we give a new
approach to count islands on a rectangular board.


title: Controlling the efficiency of trapping in treelike fractals

abstract:
  Efficiently controlling the trapping process, especially the trapping
efficiency, is central in the study of trap problem in complex systems, since
it is a fundamental mechanism for diverse other dynamic processes. Thus, it is
of theoretical and practical significance to study the control technique for
trapping problem. In this paper, we study the trapping problem in a family of
proposed directed fractals with a deep trap at a central node. The directed
fractals are a generalization of previous undirected fractals by introducing
the directed edge weights dominated by a parameter. We characterize all the
eigenvalues and their degeneracies for an associated matrix governing the
trapping process. The eigenvalues are provided through an exact recursive
relation deduced from the self-similar structure of the fractals. We also
obtain the expressions for the smallest eigenvalue and the mean first-passage
time (MFPT) as a measure of trapping efficiency, which is the expected time for
the walker to first visit the trap. The MFPT is evaluated according to the
proved fact that it is approximately equal to reciprocal of the smallest
eigenvalue. We show that the MFPT is controlled by the weight parameter, by
modifying which, the MFPT can scale superlinealy, linearly, or sublinearly with
the system size. Thus, this work paves a way to delicately controlling the
trapping process in the fractals.


title: Re-thinking the Rubric for Grading the CUE: The Superposition Principle

abstract:
  While introductory electricity and magnetism (E&M) has been investigated for
decades, research at the upper-division is relatively new. The University of
Colorado has developed the Colorado Upper-Division Electrostatics (CUE)
Diagnostic to test students' understanding of the content of the first semester
of an upper-division E&M course. While the questions on the CUE cover many
learning goals in an appropriate manner, we believe the rubric for the CUE is
particularly aligned to the topics and methods of teaching at the University of
Colorado. We suggest that changes to the rubric would allow for better
assessment of a wider range of teaching schemes. As an example, we highlight
one problem from the CUE involving the superposition principle. Using data from
both Oregon State University and the University of Colorado, we discuss the
limitations of the current rubric, compare results using a different analysis
scheme, and discuss the implications for assessing students' understanding.


title:
Random walks in weighted networks with a perfect trap: An application of
  Laplacian spectra

abstract:
  In this paper, we propose a general framework for the trapping problem on a
weighted network with a perfect trap fixed at an arbitrary node. By utilizing
the spectral graph theory, we provide an exact formula for mean first-passage
time (MFPT) from one node to another, based on which we deduce an explicit
expression for average trapping time (ATT) in terms of the eigenvalues and
eigenvectors of the Laplacian matrix associated with the weighted graph, where
ATT is the average of MFPTs to the trap over all source nodes. We then further
derive a sharp lower bound for the ATT in terms of only the local information
of the trap node, which can be obtained in some graphs. Moreover, we deduce the
ATT when the trap is distributed uniformly in the whole network. Our results
show that network weights play a significant role in the trapping process. To
apply our framework, we use the obtained formulas to study random walks on two
specific networks: trapping in weighted uncorrelated networks with a deep trap,
the weights of which are characterized by a parameter, and L\'evy random walks
in a connected binary network with a trap distributed uniformly, which can be
looked on as random walks on a weighted network. For weighted uncorrelated
networks we show that the ATT to any target node depends on the weight
parameter, that is, the ATT to any node can change drastically by modifying the
parameter, a phenomenon that is in contrast to that for trapping in binary
networks. For L\'evy random walks in any connected network, by using their
equivalence to random walks on a weighted complete network, we obtain the
optimal exponent characterizing L\'evy random walks, which have the minimal
average of ATTs taken over all target nodes.


title: Studies on an S-band Bunching System with Hybrid Buncher

abstract:
  Generally, a standard bunching system is composed by a SW pre-buncher, a TW
buncher and a standard accelerating section. However, there is one way to
simplify the whole system to some extent by using the hybrid buncher, which is
a combined structure of the SW pre-buncher and the TW buncher. Here the beam
dynamics studies on an S-band bunching system with the hybrid buncher is
presented, simulation results shows that similar beam performance can be
obtained at the linac exit by using this kind of bunching system rather than
the standard one. In the meantime, the structure design of the hybrid buncher
is also described. Furthermore, the standard accelerating section can also be
integrated with the hybrid buncher, which can further simplify the usual
bunching system and lower the construction cost.


title: Algorithm and Complexity for a Network Assortativity Measure

abstract:
  We show that finding a graph realization with the minimum Randi\'c index for
a given degree sequence is solvable in polynomial time by formulating the
problem as a minimum weight perfect b-matching problem. However, the
realization found via this reduction is not guaranteed to be connected.
Approximating the minimum weight b-matching problem subject to a connectivity
constraint is shown to be NP-Hard. For instances in which the optimal solution
to the minimum Randi\'c index problem is not connected, we describe a heuristic
to connect the graph using pairwise edge exchanges that preserves the degree
sequence. In our computational experiments, the heuristic performs well and the
Randi\'c index of the realization after our heuristic is within 3% of the
unconstrained optimal value on average. Although we focus on minimizing the
Randi\'c index, our results extend to maximizing the Randi\'c index as well.
Applications of the Randi\'c index to synchronization of neuronal networks
controlling respiration in mammals and to normalizing cortical thickness
networks in diagnosing individuals with dementia are provided.


title: Analog Superconducting Quantum Simulator for Holstein Polarons

abstract:
  We propose an analog quantum simulator for the Holstein molecular-crystal
model based on a superconducting circuit QED system in the dispersive regime.
By varying the driving field on the superconducting resonators, one can readily
access both the adiabatic and anti-adiabatic regimes of this model. Strong e-ph
coupling required for small-polaron formation can also be reached. We show that
small-polaron state of arbitrary quasimomentum can be generated by applying a
microwave pulse to the resonators. We also show that significant squeezing in
the resonator modes can be achieved in the polaron-crossover regime through a
measurement-based scheme.


title:
Time series analysis of gamma-ray blazars and implications for the
  central black-hole mass

abstract:
  Radiation from the blazar class of of active galactic nuclei (AGN) exhibits
fast time variability which is usually ascribed to instabilities in the
emission region near the central supermassive black hole. The variability time
scale is generally faster in higher energy region, and data recently provided
by the {\it Fermi} Gamma-ray Space Telescope in the GeV energy band enable a
detailed study of the temporal behavior of AGN. Due to its wide field-of-view
in the scanning mode, most sky regions are observed for several hours per day
and daily light curves of many AGN have been accumulated for more than 4 years.
  In this paper we investigate the time variability of 15 well-detected AGNs by
studying the normalized power spectrum density (NPSD) of their light curves in
the GeV energy band. One source, 3C 454.3, shows a specific time scale of
$6.8\times10^5$ s, and this value suggests, assuming the internal shock model,
a mass for the central black hole of $(10^8$--$10^{10})M_\odot$ which is
consistent with other estimates. It also indicates the typical time interval of
ejected blobs is $(7$--$70)$ times the light crossing time of the Schwarzschild
radius.


title: Slow Control Systems of the Reactor Experiment for Neutrino Oscillation

abstract:
  The RENO experiment has been in operation since August 2011 to measure
reactor antineutrino disappearance using identical near and far detectors. For
accurate measurements of neutrino mixing parameters and efficient data taking,
it is crucial to monitor and control the detector in real time. Environmental
conditions also need to be monitored for stable operation of detectors as well
as for safety reasons. In this article, we report the design, hardware,
operation, and performance of the slow control system.


title: Regular systems of paths and families of convex sets in convex position

abstract:
  In this paper we show that every sufficiently large family of convex bodies
in the plane has a large subfamily in convex position provided that the number
of common tangents of each pair of bodies is bounded and every subfamily of
size five is in convex position. (If each pair of bodies have at most two
common tangents it is enough to assume that every triple is in convex position,
and likewise, if each pair of bodies have at most four common tangents it is
enough to assume that every quadruple is in convex position.) This confirms a
conjecture of Pach and Toth, and generalizes a theorem of Bisztriczky and Fejes
Toth. Our results on families of convex bodies are consequences of more general
Ramsey-type results about the crossing patterns of systems of graphs of
continuous functions $f:[0,1] \to \mathbb{R}$. On our way towards proving the
Pach-Toth conjecture we obtain a combinatorial characterization of such systems
of graphs in which all subsystems of equal size induce equivalent crossing
patterns. These highly organized structures are what we call regular systems of
paths and they are natural generalizations of the notions of cups and caps from
the famous theorem of Erdos and Szekeres. The characterization of regular
systems is combinatorial and introduces some auxiliary structures which may be
of independent interest.


title: Non-polynomial extensions of solvable potentials a la Abraham-Moses

abstract:
  Abraham-Moses transformations, besides Darboux transformations, are
well-known procedures to generate extensions of solvable potentials in
one-dimensional quantum mechanics. Here we present the explicit forms of
infinitely many seed solutions for adding eigenstates at arbitrary real energy
through the Abraham-Moses transformations for typical solvable potentials, e.g.
the radial oscillator, the Darboux-P\"oschl-Teller and some others. These seed
solutions are simple generalisations of the virtual state wavefunctions, which
are obtained from the eigenfunctions by discrete symmetries of the potentials.
The virtual state wavefunctions have been an essential ingredient for
constructing multi-indexed Laguerre and Jacobi polynomials through multiple
Darboux-Crum transformations. In contrast to the Darboux transformations, the
virtual state wavefunctions generate non-polynomial extensions of solvable
potentials through the Abraham-Moses transformations.

categories: math-ph hep-th math.CA math.MP nlin.SI quant-ph


title: Fractal patterns related to dividing coins

abstract:
  The present paper formulates and solves a problem of dividing coins. The
basic form of the problem seeks the set of the possible ways of dividing coins
of face values 1,2,4,8,... between three people. We show that this set
possesses a nested structure like the Sierpinski-gasket fractal. For a set of
coins with face values power of r, the number of layer of the gasket becomes r.
A higher-dimensional Sierpinski gasket is obtained if the number of people is
more than three. In addition to Sierpinski-type fractals, the Cantor set is
also obtained in dividing an incomplete coin set between two people.


title:
Gender gap on concept inventories in physics: what is consistent, what
  is inconsistent, and what factors influence the gap?

abstract:
  We review the literature on the gender gap on concept inventories in physics.
Across studies of the most commonly used mechanics concept inventories, the
Force Concept Inventory (FCI) and Force and Motion Conceptual Evaluation
(FMCE), mens average pretest scores are always higher than womens, and in most
cases mens posttest scores are higher as well. The weighted average gender
difference on these tests is 13% for pretest scores, 12% for posttest scores,
and 6% for normalized gain. This difference is much smaller than the average
difference in normalized gain between traditional lecture and interactive
engagement (25%), but it is large enough that it could impact the results of
studies comparing the effectiveness of different teaching methods. There is
sometimes a gender gap on commonly used electromagnetism concept inventories,
but it is usually much smaller and sometimes is zero or favors women. The
weighted average gender difference on these tests is 3.7% for pretest scores,
8.5% for posttest scores, and 6% for normalized gain. Based on our analysis of
26 published articles, no single factor is sufficient to explain the gap.
Several high-profile studies that have claimed to account for or reduce the
gender gap have failed to be replicated in subsequent studies, suggesting that
isolated claims of explanations of the gender gap should be interpreted with
caution. Other factors, such as gender differences in background preparation,
scores on different kinds of assessment, and splits between how students
respond to test questions when answering for themselves or for a scientist do
contribute to a difference between male and female responses, but the size of
these differences is smaller than the size of the overall gender gap,
suggesting that the gender gap is most likely due to the combination of many
small factors rather than any one factor that can easily be modified.


title: New Proofs for Several Properties of Capacities

abstract:
  In this note, we find a new way to prove several properties of 2-alternating
capacities.


title:
On Consistency of Finite Difference Approximations to the Navier-Stokes
  Equations

abstract:
  In the given paper, we confront three finite difference approximations to the
Navier--Stokes equations for the two-dimensional viscous incomressible fluid
flows. Two of these approximations were generated by the computer algebra
assisted method proposed based on the finite volume method, numerical
integration, and difference elimination. The third approximation was derived by
the standard replacement of the temporal derivatives with the forward
differences and the spatial derivatives with the central differences. We prove
that only one of these approximations is strongly consistent with the
Navier--Stokes equations and present our numerical tests which show that this
approximation has a better behavior than the other two.


title:
Separation of cardiac and respiratory components from the electrical
  bio-impedance signal using PCA and fast ICA

abstract:
  This paper is an attempt to separate cardiac and respiratory signals from an
electrical bio-impedance (EBI) dataset. For this two well-known algorithms,
namely Principal Component Analysis (PCA) and Independent Component Analysis
(ICA), were used to accomplish the task. The ability of the PCA and the ICA
methods first reduces the dimension and attempt to separate the useful
components of the EBI, the cardiac and respiratory ones accordingly. It was
investigated with an assumption, that no motion artefacts are present. To carry
out this procedure the two channel complex EBI measurements were provided using
classical Kelvin type four electrode configurations for the each complex
channel. Thus four real signals were used as inputs for the PCA and fast ICA.
The results showed, that neither PCA nor ICA nor combination of them can not
accurately separate the components at least are used only two complex (four
real valued) input components.


title:
Density Independent Smoothed Particle Hydrodynamics for Non-Ideal
  Equation of State

abstract:
  The smoothed particle hydrodynamics (SPH) method is a useful numerical tool
for the study of a variety of astrophysical and planetlogical problems.
However, it turned out that the standard SPH algorithm has problems in dealing
with hydrodynamical instabilities. This problem is due to the assumption that
the local density distribution is differentiable. In order to solve this
problem, a new SPH formulation, which does not require the differentiability of
the density, have been proposed. This new SPH method improved the treatment of
hydrodynamical instabilities. This method, however, is applicable only to the
equation of state (EOS) of the ideal gas. In this paper, we describe how to
extend the new SPH method to non-ideal EOS. We present the results of various
standard numerical tests for non-ideal EOS. Our new method works well for
non-ideal EOS. We conclude that our new SPH can handle hydrodynamical
instabilities for an arbitrary EOS and that it is an attractive alternative to
the standard SPH.


title:
L2-orthogonal projections onto finite elements on locally refined meshes
  are H1-stable

abstract:
  We merge and extend recent results which prove the H1-stability of the
L2-orthogonal projection onto standard finite element spaces, provided that the
underlying simplicial triangulation is appropriately graded. For lowest-order
Courant finite elements S1(T) in Rd with d>=2, we prove that such a grading is
always ensured for adaptive meshes generated by newest vertex bisection. For
higher-order finite elements Sp(T) with p>=1, we extend existing bounds on the
polynomial degree with a computer-assisted proof. We also consider
L2-orthogonal projections onto certain subspaces of Sp(T) which incorporate
zero Dirichlet boundary conditions resp. an integral mean zero property.


title:
Directed Riemannian manifolds of pointwise constant relative sectional
  curvature

abstract:
  We study a class of Riemannian manifolds with respect to the covariant
derivative of their curvature tensors. We introduce geometrically the class of
directed Riemannian manifolds of pointwise constant relative sectional
curvature and give a tensor characterization for such manifolds. We prove that
all rotational hypersurfaces are directed and find the rotational hypersurfaces
of pointwise constant relative sectional curvature. For the class of directed
Riemannian manifolds of pointwise constant relative sectional curvature having
a totally umbilical scalar distribution we prove a structural theorem and a
theorem of Schur's type.


title:
New clues on the nature of the companion to PSR~J1740-5340 in NGC6397
  from XSHOOTER spectroscopy

abstract:
  By using XSHOOTER spectra acquired at the ESO Very Large Telescope, we have
studied the surface chemical composition of the companion star to the binary
millisecond pulsar PSR J1740-5340 in the globular cluster NGC 6397. The
measured abundances of Fe, Mg, Al and Na confirm that the star belongs to the
cluster. On the other hand, the measured surface abundance of nitrogen
([N/Fe]=+0.53 +- 0.15 dex) combined with the carbon upper limit ([C/Fe] <-2
dex) previously obtained from UVES spectra allow us to put severe constraints
on its nature, strongly suggesting that the pulsar companion is a deeply peeled
star. In fact, the comparison with theoretical stellar models indicates that
the matter currently observed at the surface of this star has been processed by
the hydrogen-burning CN-cycle at equilibrium. In turn, this evidence suggests
that the pulsar companion is a low mass (~0.2 Msun) remnant star, descending
from a ~0.8 Msun progenitor which lost ~70-80 % of its original material
because of mass transfer activity onto the pulsar.


title: Domain Specific Hierarchical Huffman Encoding

abstract:
  In this paper, we revisit the classical data compression problem for domain
specific texts. It is well-known that classical Huffman algorithm is optimal
with respect to prefix encoding and the compression is done at character level.
Since many data transfer are domain specific, for example, downloading of
lecture notes, web-blogs, etc., it is natural to think of data compression in
larger dimensions (i.e. word level rather than character level). Our framework
employs a two-level compression scheme in which the first level identifies
frequent patterns in the text using classical frequent pattern algorithms. The
identified patterns are replaced with special strings and to acheive a better
compression ratio the length of a special string is ensured to be shorter than
the length of the corresponding pattern. After this transformation, on the
resultant text, we employ classical Huffman data compression algorithm. In
short, in the first level compression is done at word level and in the second
level it is at character level. Interestingly, this two level compression
technique for domain specific text outperforms classical Huffman technique. To
support our claim, we have presented both theoretical and simulation results
for domain specific texts.


title:
The correlation of 27 day period solar activity and daily maximum
  temperature in continental Australia

abstract:
  We report the first observation of a 27 day period component in daily maximum
temperature recorded at widely spaced locations in Australia. The 27 day
component, extracted by band pass filtering, is correlated with the variation
of daily solar radio flux during years close to solar minimum. We demonstrate
that the correlation is related to the emergence of regions of solar activity
on the Sun separated, temporally, from the emergence of other active regions.
In this situation, which occurs only near solar minimum, the observed 27 day
variation of temperature can be in phase or out of phase with the 27 day
variation of solar activity. During solar maximum correlation of temperature
and solar activity is much less defined. The amplitude of the 27 day
temperature response to solar activity is large, at times as high as 6 degrees
C, and much larger than the well documented temperature response to the 11 year
cycle of solar activity. We demonstrate that the 27 day temperature response is
localised to the Australian continent and increases towards the centre of the
continent. Several aspects of the 27 day temperature response are consistent
with a 27 day period solar input to the Earth continents generating large scale
planetary waves.


title:
SU(3) Dirac electrons in the 1/5-depleted square-lattice Hubbard model
  at 1/4 filling

abstract:
  We investigate the magnetic and metal-insulator (M-I) phase diagram of the
1/5-depleted square-lattice Hubbard model at 1/4 filling by the mean-field
approximation. There exist three magnetic phases of nonmagnetic (N),
antiferromagnetic (AF), and ferromagnetic (F) types, each realized for the
large intrasquare hopping t1, intersquare hopping t2, and Coulomb interaction
U, respectively. Within each magnetic phase, the M-I transition of Lifshitz
type emerges and, finally, six kind of phases are identified in the U-t1/t2
plane. When t1=t2, we find that the Dirac cone and nearly flat band around the
Gamma point form the SU(3) multiplet. The SU(3) effective theory well describes
the phase transitions between NI, paramagnetic-metal (PM), and AF phases. The
NI and AFI phases are characterized by different Berry phases as in
polyacetylene or graphene.


title: Tunneling spectrum of a pinned vortex with a robust Majorana state

abstract:
  We study a heterostructure which consists of a topological insulator and a
superconductor with a hole. The hole pins a vortex. The system supports a
robust Majorana fermion state bound to the vortex core. We investigate the
possibility of using scanning tunneling spectroscopy (i) to detect the Majorana
fermion in the proposed setup and (ii) to study excited states bound to the
vortex core. The Majorana fermion manifests itself as a magnetic-field
dependent zero-bias anomaly of the tunneling conductance. Optimal parameters
for detecting Majorana fermions have been obtained. In the optimal regime, the
Majorana fermion is separated from the excited states by a substantial gap. The
number of zero-energy states equals the number of flux quanta in the hole;
thus, the strength of the zero-bias anomaly depends on the magnetic field. The
lowest energy excitations bound to the core are also studied. The excited
states spectrum differs from the spectrum of a typical Abrikosov vortex,
providing additional indirect confirmation of the Majorana state observation.


title: Beurling's Theorem And Invariant Subspaces For The Shift On Hardy Spaces

abstract:
  Let $G$ be a bounded open subset in the complex plane and let $H^{2}(G)$
denote the Hardy space on $G$. We call a bounded simply connected domain $W$
perfectly connected if the boundary value function of the inverse of the
Riemann map from $W$ onto the unit disk $D$ is almost 1-1 rwith respect to the
Lebesgure on $\partial D$ and if the Riemann map belongs to the weak-star
closure of the polynomials in $H^{\infty}(W)$. Our main theorem states: In
order that for each $M\in Lat(M_{z})$, there exist $u\in H^{\infty}(G)$ such
that $ M = \vee\{u H^{2}(G)\}$, it is necessary and sufficient that the
following hold:
  1) Each component of $G$ is a perfectly connected domain.
  2) The harmonic measures of the components of $G$ are mutually singular.
  3) % $P^{\infty}(\omega)
  The set of polynomials is weak-star dense in $ H^{\infty}(G)$.
  \noindent Moreover, if $G$ satisfies these conditions, then every $M\in
Lat(M_{z})$ is of the form $u H^{2}(G)$, where %$u\in H^{\infty}(G)$ and the
restriction of $u$ to each of the components of $G$ is either an inner function
or zero.


title: Almost Ballistic Transport for the Weakly Coupled Fibonacci Hamiltonian

abstract:
  We prove estimates for the transport exponents associated with the weakly
coupled Fibonacci Hamiltonian. It follows in particular that the upper
transport exponent $\tilde \alpha^\pm_u$ approaches the value one as the
coupling goes to zero. Moreover, for sufficiently small coupling, $\tilde
\alpha^\pm_u$ strictly exceeds the fractal dimension of the spectrum.


title:
Simple approach for detection and estimation of photoactivity of silver
  particles on graphene oxide in aqueous-organic dispersion

abstract:
  In the aqueous-organic (containing dimethylformamide) dispersion of graphene
oxide flakes with deposited thereon Ag-particles, under the action of light in
visible range, apparently for the first time, the effect of sediment flotation
was observed with subsequent stabilization of the dispersion, which does not
occur in the absence of Ag-particles. The main reason for such a laser light
induced movement of sediment GO flakes may be explained with the appearance of
small bubbles. The further development of this approach seem to be able to
estimate photo activity of graphene flakes with different activation particles.


title:
On the bounds and achievability about the ODPC of $\mathcal{GRM}(2,m)^*$
  over prime field for increasing message length

abstract:
  The optimum distance profiles of linear block codes were studied for
increasing or decreasing message length while keeping the minimum distances as
large as possible, especially for Golay codes and the second-order Reed-Muller
codes, etc. Cyclic codes have more efficient encoding and decoding algorithms.
In this paper, we investigate the optimum distance profiles with respect to the
cyclic subcode chains (ODPCs) of the punctured generalized second-order
Reed-Muller codes $\mathcal{GRM}(2,m)^*$ which were applied in Power Control in
OFDM Modulations in channels with synchronization, and so on. For this, two
standards are considered in the inverse dictionary order, i.e., for increasing
message length. Four lower bounds and upper bounds on ODPC are presented, where
the lower bounds almost achieve the corresponding upper bounds in some sense.
The discussions are over nonbinary prime field.


title: Galactic Constraints on Supernova Progenitor Models

abstract:
  We undertake a statistical analysis of the radial abundance distributions in
the Galactic disk within a theoretical framework for Galactic chemical
evolution which incorporates the influence of spiral arms. 1) The mean mass of
oxygen ejected per core-collapse SNe (CC SNe) event (which are concentrated
within spiral arms) is $\sim$0.27 M$_{\odot}$; 2) the mean mass of iron ejected
by `tardy' Type Ia SNe (SNeIa; progenitors of whom are older/longer-lived stars
with ages $\simgt$100 Myr and up to several Gyr, which do not concentrate
within spiral arms) is $\sim$0.58 M$_{\odot}$; 3) the upper mass of iron
ejected by prompt SNeIa (SNe whose progenitors are younger/shorter-lived stars
with ages $\simlt$100 Myr, which are concentrated within spiral arms) is
$\leq$0.23 M$_{\odot}$ per event; 4) the corresponding mean mass of iron
produced by CC SNe is $\leq$0.04 M$_{\odot}$ per event; (v) short-lived SNe
(core-collapse or prompt SNeIa) supply $\sim$85% of the Galactic disk's iron.
  The inferred low mean mass of oxygen ejected per CC SNe event implies a low
upper mass limit for the corresponding progenitors of $\sim$23 M$_{\odot}$,
otherwise the Galactic disk would be overabundant in oxygen.
  The low mean mass of iron ejected by prompt SNeIa, relative to the mass
produced by tardy SNeIa ($\sim$2.5 times lower), prejudices the idea that both
sub-populations of SNeIa have the same physical nature. We suggest that,
perhaps, prompt SNeIa are more akin to CC SNe, and discuss the implications of
such a suggestion.


title: Electronic crystals: an experimental overview

abstract:
  This article reviews the static and dynamic properties of spontaneous
superstructures formed by electrons. Representations of such electronic
crystals are charge density waves and spin density waves in inorganic as well
as organic low dimensional materials. A special attention is paid to the
collective effects in pinning and sliding of these superstructures, and the
glassy properties at low temperature. Charge order and charge
disproportionation which occur in organic materials resulting from correlation
effects are analysed. Experiments under magnetic field, and more specifically
field-induced charge density waves are discussed. Properties of meso- and
nanostructures of charge density waves are also reviewed.


title:
On the filtering effect of iterative regularization algorithms for
  linear least-squares problems

abstract:
  Many real-world applications are addressed through a linear least-squares
problem formulation, whose solution is calculated by means of an iterative
approach. A huge amount of studies has been carried out in the optimization
field to provide the fastest methods for the reconstruction of the solution,
involving choices of adaptive parameters and scaling matrices. However, in
presence of an ill-conditioned model and real data, the need of a regularized
solution instead of the least-squares one changed the point of view in favour
of iterative algorithms able to combine a fast execution with a stable
behaviour with respect to the restoration error. In this paper we want to
analyze some classical and recent gradient approaches for the linear
least-squares problem by looking at their way of filtering the singular values,
showing in particular the effects of scaling matrices and non-negative
constraints in recovering the correct filters of the solution.


title:
A novel scheme for measuring the relative phase difference between S and
  P polarization in optically denser medium

abstract:
  We demonstrate applications of a novel setup which is used for measuring
relative phase difference between S and P polarization at oblique incidence
point in optically denser medium by analyzing the relative frequency shift of
adjacent axial modes of S and P resonances of a monolithic folded Fabry-Perot
cavity (MFC). The relative frequency shift of adjacent axial modes of S and P
resonances of MFC is around 1.030 GHz for the confocal MFC cavity and 0.3869
GHz for the parallel MFC cavity respectively. The relative phase difference at
reflection point A in optically denser medium is inferred to be around
-167.4{\deg} for confocal cavity and -201.1{\deg} for parallel cavity
separately. This scheme can be used to measure the relative phase difference in
optically denser mediums which is out of measuring range of Ellipsometry.


title:
Investigation of coupling geometry and dimerization effects on
  thermoelectric properties of a C60 molecular transistor

abstract:
  Thermoelectric properties of a C60 molecular transistor are studied using
Green function formalism in linear response regime. A tight-binding model is
used to investigate the effect of the dimerization and coupling geometry on the
electrical conductance, thermopower, and figure of merit. Increase of the
connection points between the molecule and electrodes results in decrease of
the number of the peaks of the electrical conductance owing to the interference
effects. In addition, oscillation of the thermopower is reduced by increase of
the connection points. It is also observed that the kind of carriers
participating in the energy transport is dependent on the coupling geometry.
Results show that the increase of the connection points leads to the reduction
of the figure of merit.


title: Validation of Geant4 simulation of electron energy deposition

abstract:
  Geant4-based simulations of the energy deposited by electrons in various
materials are quantitatively compared to high precision calorimetric
measurements taken at Sandia Laboratories. The experimental data concern
electron beams of energy between a few tens of keV and 1 MeV at various
incidence angles. Two experimental scenarios are evaluated: the longitudinal
energy deposition pattern in a finely segmented detector, and the total energy
deposited in a larger size calorimeter. The simulations are produced with
Geant4 versions from 9.1 to 9.6; they involve models of electron-photon
interactions in the standard and low energy electromagnetic packages, and
various implementations of electron multiple scattering. Significant
differences in compatibility with experimental data are observed in the
longitudinal energy deposition patterns produced by the examined Geant4
versions, while the total deposited energy exhibits smaller variations across
the various Geant4 versions, with the exception Geant4 9.4. The validation
analysis, based on statistical methods, shows that the best compatibility
between simulation and experimental energy deposition profiles is achieved
using electromagnetic models based on the EEDL and EPDL evaluated data
libraries with Geant4 9.1. The results document the accuracy achievable in the
simulation of the energy deposited by low energy electrons with Geant4; they
provide guidance for application in similar experimental scenarios and for
improving Geant4.


title:
Nuclear equation of state in a relativistic independent quark model with
  chiral symmetry and variation with quark masses

abstract:
  We have calculated the properties of nuclear matter in a self-consistent
manner with quark-meson coupling mechanism incorporating structure of nucleons
in vacuum through a relativistic potential model; where the dominant confining
interaction for the free independent quarks inside a nucleon, is represented by
a phenomenologically average potential in equally mixed scalar-vector harmonic
form. Corrections due to spurious centre of mass motion as well as those due to
other residual interactions such as the one gluon exchange at short distances
and quark-pion coupling arising out of chiral symmetry restoration; have been
considered in a perturbation manner to obtain the nucleon mass in vacuum. The
nucleon-nucleon interaction in nuclear matter is then realized by introducing
additional quark couplings to sigma and omega mesons through mean field
approximations. The relevant parameters of the interaction are obtained self
consistently while realizing the saturation properties such as the binding
energy, pressure and compressibility of the nuclear matter. We also discuss
some implications of chiral symmetry in nuclear matter along with the nucleon
and nuclear sigma term and the sensitivity of nuclear matter binding energy
with variations in the light quark mass.


title:
Low temperature rate constants for the N(4S) + CH(X2{\Pi}r) reaction.
  Implications for N2 formation cycles in dense interstellar clouds

abstract:
  Rate constants for the potentially important interstellar N(4S) +
CH(X2{\Pi}r) reaction have been measured in a continuous supersonic flow
reactor over the range 56 K < T < 296 K using the relative rate technique
employing both the N(4S) + OH(X2{\Pi}i) and N(4S) + CN(X2{\Sigma}+) reactions
as references. Excess concentrations of atomic nitrogen were produced by the
microwave discharge method upstream of the Laval nozzle and CH and OH radicals
were created by the in-situ pulsed laser photolysis of suitable precursor
molecules. In parallel, quantum dynamics calculations of the title reaction
have been performed based on accurate global potential energy surfaces for the
13A' and 13A" states of HCN and HNC, brought about through a hierarchical
construction scheme. Both adiabatic potential energy surfaces are barrierless,
each one having two deep potential wells suggesting that this reaction is
dominated by a complex-forming mechanism. The experimental and theoretical work
are inexcellent agreement, predicting a positive temperature dependence of the
rate constant, in contrast to earlier experimental work at low temperature. The
effects of the new low temperature rate constants on interstellar N2 formation
are tested using a dense cloud model, yielding N2 abundances 10-20 % lower than
previously predicted.


title:
Isoscalar amplitude dominance in $e^+e-$ annihilation to $N\bar{N}$ pair
  close to the threshold

abstract:
  We use the Paris nucleon-antinucleon optical potential for explanation of
experimental data in the process $e^+e^- \rightarrow p\bar p$ near threshold.
It turns out that final-state interaction due to Paris optical potential allows
us to reproduce available experimental data. It follows from our consideration
that the isoscalar form factor is much larger than the isovector one.


title: Extending UML for Conceptual Modeling of Annotation of Medical Images

abstract:
  Imaging has occupied a huge role in the management of patients, whether
hospitalized or not. Depending on the patients clinical problem, a variety of
imaging modalities were available for use. This gave birth of the annotation of
medical image process. The annotation is intended to image analysis and solve
the problem of semantic gap. The reason for image annotation is due to increase
in acquisition of images. Physicians and radiologists feel better while using
annotation techniques for faster remedy in surgery and medicine due to the
following reasons: giving details to the patients, searching the present and
past records from the larger databases, and giving solutions to them in a
faster and more accurate way. However, classical conceptual modeling does not
incorporate the specificity of medical domain specially the annotation of
medical image. The design phase is the most important activity in the
successful building of annotation process. For this reason, we focus in this
paper on presenting the conceptual modeling of the annotation of medical image
by defining a new profile using the StarUML extensibility mechanism.


title: Changepoint detection for dependent Gaussian sequences

abstract:
  In this paper easily applicable techniques are devised for detecting
changepoints in autocorrelated Gaussian sequences. Our method proceeds by
sequential evaluation of a CUSUM-type test statistic, which is compared to a
predefined threshold. We assume that data is tested in sliding windows of fixed
size. The distinguishing feature of this work is that, based on large
deviations theory, we derive rather explicit equations that determine the
threshold in such a way that the false alarm probability per window is
approximately kept at the desired level. This criterion -- as opposed to the
usual average run length -- allows to restrict not only the average number of
false alarms but also their variability. Illustrative examples are provided,
including the detection of a shift in mean in ARMA processes. The procedures
are validated by means of a broad set of simulation experiments, and overall
perform well.


title:
A global mirror symmetry framework for the Landau-Ginzburg/Calabi-Yau
  correspondence

abstract:
  We show how the Landau-Ginzburg/Calabi-Yau correspondence for the quintic
three-fold can be cast into a global mirror symmetry framework. Then we draw
inspiration from Berglund-H\"ubsch mirror duality construction to provide an
analogue conjectural picture featuring all Calabi-Yau hypersurfaces within
weighted projective spaces and certain quotients by finite abelian group
actions.


title:
Enhanced Hot-Carrier Luminescence in Multilayer Reduced Graphene Oxide
  Nanospheres

abstract:
  We report a method to promote photoluminescence emission in graphene
materials by enhancing carrier scattering instead of directly modifying band
structure in multilayer reduced graphene oxide (rGO) nanospheres. We
intentionally curl graphene layers to form nanospheres by reducing graphene
oxide with spherical polymer templates to manipulate the carrier scattering.
These nanospheres produce hot-carrier luminescence with more than ten-fold
improvement of emission efficiency as compared to planar nanosheets. With
increasing excitation power, hot-carrier luminescence from nanospheres exhibits
abnormal spectral redshift with dynamic feature associated to the strengthened
electron-phonon coupling. These experimental results can be well understood by
considering the screened Coulomb interactions. With increasing carrier density,
the reduced screening effect promotes carrier scattering which enhances
hot-carrier emission from such multilayer rGO nanospheres. This
carrier-scattering scenario is further confirmed by pump-probe measurements.


title: Generation of a fully valley-polarized current in bulk graphene

abstract:
  The generation of a fully valley-polarized current (FVPC) in bulk graphene is
a fundamental goal in valleytronics. To this end, we investigate
valley-dependent transport through a strained graphene modulated by a finite
magnetic superlattice. It is found that this device allows a coexistence of
insulating transmission gap of one valley and metallic resonant band of the
other. Accordingly, a substantial bulk FVPC appears in a wide range of edge
orientation and temperature, which can be effectively tuned by structural
parameters. A valley-resolved Hall configuration is designed to measure the
valley polarization degree of the filtered current.


title:
Extraction of the Solvation Structure on a Solid Plate from a force
  curve measured by Surface Force Apparatus in a hard-sphere fluid

abstract:
  We propose a method of transformation from a force curve obtained with a
surface force apparatus (SFA) to a density distribution of a liquid near a
surface. The method is based on the statistical mechanics of liquids. As a
first step, we show the method for a rigid system in which two cylinders are
immersed in a hard-sphere fluid as the force probes. We found that the method
works well, especially in the lower density solvent. The accuracy of the
transformed result increases as the distance between the circular surface of
the cylinder and the solvent sphere increases.

categories: physics.data-an physics.bio-ph physics.chem-ph physics.comp-ph