title:
Electron propagation from a photo-excited surface: implications for
  time-resolved photoemission

abstract:
  We perform time- and angle-resolved photoelectron spectroscopy on p-type
GaAs(110). We observe an optically excited population in the conduction band,
from which the time scales of intraband relaxation and surface photovoltage
decay are both extracted. Moreover, the photovoltage shift of the valence band
intriguingly persists for hundreds of picoseconds at negative delays. By
comparing to a recent theoretical study, we reveal that the negative-delay
dynamics reflects the interaction of the photoelectrons with a
photovoltage-induced electric field outside the sample surface. We develop a
conceptual framework to disentangle the intrinsic electron dynamics from this
long-range field effect, which sets the foundation for understanding
time-resolved photoemission experiments on a broad range of materials in which
poor electronic screening leads to surface photovoltage. Finally, we
demonstrate how the long-lasting negative-delay dynamics in GaAs can be
utilized to conveniently establish the temporal overlap of pump and probe
pulses in a time-resolved photoemission setup.


title: Flavour and Higgs physics near the Fermi scale

abstract:
  After a discussion of the hierarchy problem of the Fermi scale, we study the
flavour and Higgs boson(s) phenomenology of new physics close to it, both in
general and in the specific cases of Supersymmetry and composite Higgs models.
First, we promote the approximate U(2)^3 symmetry exhibited by the quark sector
of the Standard Model to be a more fundamental symmetry of Nature, and explore
its phenomenological consequences from an effective field theory point of view.
We also study the embedding of natural Supersymmetry within the U(2)^3
framework, focusing in particular on the pattern of flavour and CP violation in
B decays. Then we consider the CP-even scalar sector of the next-to-minimal
supersymmetric Standard Model. We quantify the impact of current and foreseen
measurements of the Higgs boson signal strengths on the physical parameters,
deriving analytical relations for this purpose, and we outline a possible
overall strategy to search for the other Higgs scalars. Finally we analyze the
constraints from flavour and electroweak precison tests on composite Higgs
models, for different representations of the composite fermions, and comparing
the case of an anarchic flavour structure to models with a U(3)^3 and a U(2)^3
flavour symmetry.


title: Incentive Design and Utility Learning via Energy Disaggregation

abstract:
  The utility company has many motivations for modifying energy consumption
patterns of consumers such as revenue decoupling and demand response programs.
We model the utility company--consumer interaction as a principal--agent
problem. We present an iterative algorithm for designing incentives while
estimating the consumer's utility function. Incentives are designed using the
aggregated as well as the disaggregated (device level) consumption data. We
simulate the iterative control (incentive design) and estimation (utility
learning and disaggregation) process for examples including the design of
incentives based on the aggregate consumption data as well as the disaggregated
consumption data.


title:
Error-prone polymerase activity causes multinucleotide mutations in
  humans

abstract:
  About 2% of human genetic polymorphisms have been hypothesized to arise via
multinucleotide mutations (MNMs), complex events that generate SNPs at multiple
sites in a single generation. MNMs have the potential to accelerate the pace at
which single genes evolve and to confound studies of demography and selection
that assume all SNPs arise independently. In this paper, we examine clustered
mutations that are segregating in a set of 1,092 human genomes, demonstrating
that MNMs become enriched as large numbers of individuals are sampled. We
leverage the size of the dataset to deduce new information about the allelic
spectrum of MNMs, estimating the percentage of linked SNP pairs that were
generated by simultaneous mutation as a function of the distance between the
affected sites and showing that MNMs exhibit a high percentage of transversions
relative to transitions. These findings are reproducible in data from multiple
sequencing platforms. Among tandem mutations that occur simultaneously at
adjacent sites, we find an especially skewed distribution of ancestral and
derived dinucleotides, with $\textrm{GC}\to \textrm{AA}$, $\textrm{GA}\to
\textrm{TT}$ and their reverse complements making up 36% of the total. These
same mutations dominate the spectrum of tandem mutations produced by the
upregulation of low-fidelity Polymerase $\zeta$ in mutator strains of S.
cerevisiae that have impaired DNA excision repair machinery. This suggests that
low-fidelity DNA replication by Pol $\zeta$ is at least partly responsible for
the MNMs that are segregating in the human population, and that useful
information about the biochemistry of MNM can be extracted from ordinary
population genomic data. We incorporate our findings into a mathematical model
of the multinucleotide mutation process that can be used to correct
phylogenetic and population genetic methods for the presence of MNMs.


title:
A complete classification of threshold properties for one-dimensional
  discrete Schr\"{o}dinger operators

abstract:
  We consider the discrete one-dimensional Schr\"{o}dinger operator $H=H_0+V$,
where $(H_0x)[n]=-(x[n+1]+x[n-1]-2x[n])$ and $V$ is a self-adjoint operator on
$\ell^2(\mathbb{Z})$ with a decay property given by $V$ extending to a compact
operator from $\ell^{\infty,-\beta}(\mathbb{Z})$ to
$\ell^{1,\beta}(\mathbb{Z})$ for some $\beta\geq1$. We give a complete
description of the solutions to $Hx=0$, and $Hx=4x$,
$x\in\ell^{\infty,-\beta}(\mathbb{Z})$. Using this description we give
asymptotic expansions of the resolvent of $H$ at the two thresholds $0$ and
$4$. One of the main results is a precise correspondence between the solutions
to $Hx=0$ and the leading coefficients in the asymptotic expansion of the
resolvent around $0$. For the resolvent expansion we implement the expansion
scheme of Jensen-Nenciu \cite{JN0, JN1} in the full generality.


title:
A Passivity Framework for Modeling and Mitigating Wormhole Attacks on
  Networked Control Systems

abstract:
  Networked control systems consist of distributed sensors and actuators that
communicate via a wireless network. The use of an open wireless medium and
unattended deployment leaves these systems vulnerable to intelligent
adversaries whose goal is to disrupt the system performance. In this paper, we
study the wormhole attack on a networked control system, in which an adversary
establishes a link between two distant regions of the network by using either
high-gain antennas, as in the out-of-band wormhole, or colluding network nodes
as in the in-band wormhole. Wormholes allow the adversary to violate the timing
constraints of real-time control systems by delaying or dropping packets, and
cannot be detected using cryptographic mechanisms alone. We study the impact of
the wormhole attack on the network flows and delays and introduce a
passivity-based control-theoretic framework for modeling the wormhole attack.
We develop this framework for both the in-band and out-of-band wormhole attacks
as well as complex, hereto-unreported wormhole attacks consisting of arbitrary
combinations of in-and out-of band wormholes. We integrate existing mitigation
strategies into our framework, and analyze the throughput, delay, and stability
properties of the overall system. Through simulation study, we show that, by
selectively dropping control packets, the wormhole attack can cause
disturbances in the physical plant of a networked control system, and
demonstrate that appropriate selection of detection parameters mitigates the
disturbances due to the wormhole while satisfying the delay constraints of the
physical system.


title:
Trust Region Subproblem with a Fixed Number of Additional Linear
  Inequality Constraints has Polynomial Complexity

abstract:
  The trust region subproblem with a fixed number m additional linear
inequality constraints, denoted by (Tm), have drawn much attention recently.
The question as to whether Problem (Tm) is in Class P or Class NP remains open.
So far, the only affirmative general result is that (T1) has an exact SOCP/SDP
reformulation and thus is polynomially solvable. By adopting an early result of
Martinez on local non-global minimum of the trust region subproblem, we can
inductively reduce any instance in (Tm) to a sequence of trust region
subproblems (T0). Although the total number of (T0) to be solved takes an
exponential order of m, the reduction scheme still provides an argument that
the class (Tm) has polynomial complexity for each fixed m. In contrast, we show
by a simple example that, solving the class of extended trust region
subproblems which contains more linear inequality constraints than the problem
dimension; or the class of instances consisting of an arbitrarily number of
linear constraints is NP-hard. When m is small such as m = 1,2, our inductive
algorithm should be more efficient than the SOCP/SDP reformulation since at
most 2 or 5 subproblems of (T0), respectively, are to be handled. In the end of
the paper, we improve a very recent dimension condition by Jeyakumar and Li
under which (Tm) admits an exact SDP relaxation. Examples show that such an
improvement can be strict indeed.


title: Handling Algebraic Effects

abstract:
  Algebraic effects are computational effects that can be represented by an
equational theory whose operations produce the effects at hand. The free model
of this theory induces the expected computational monad for the corresponding
effect. Algebraic effects include exceptions, state, nondeterminism,
interactive input/output, and time, and their combinations. Exception handling,
however, has so far received no algebraic treatment. We present such a
treatment, in which each handler yields a model of the theory for exceptions,
and each handling construct yields the homomorphism induced by the universal
property of the free model. We further generalise exception handlers to
arbitrary algebraic effects. The resulting programming construct includes many
previously unrelated examples from both theory and practice, including
relabelling and restriction in Milner's CCS, timeout, rollback, and stream
redirection.


title:
A Revisit to Quadratic Programming with One Inequality Quadratic
  Constraint via Matrix Pencil

abstract:
  The quadratic programming over one inequality quadratic constraint (QP1QC) is
a very special case of quadratically constrained quadratic programming (QCQP)
and attracted much attention since early 1990's. It is now understood that,
under the primal Slater condition, (QP1QC) has a tight SDP relaxation (PSDP).
The optimal solution to (QP1QC), if exists, can be obtained by a matrix rank
one decomposition of the optimal matrix X? to (PSDP). In this paper, we pay a
revisit to (QP1QC) by analyzing the associated matrix pencil of two symmetric
real matrices A and B, the former matrix of which defines the quadratic term of
the objective function whereas the latter for the constraint. We focus on the
\undesired" (QP1QC) problems which are often ignored in typical literature:
either there exists no Slater point, or (QP1QC) is unbounded below, or (QP1QC)
is bounded below but unattainable. Our analysis is conducted with the help of
the matrix pencil, not only for checking whether the undesired cases do happen,
but also for an alternative way to compute the optimal solution in comparison
with the usual SDP/rank-one-decomposition procedure.


title: Modeling Epidermis Homeostasis and Psoriasis Pathogenesis

abstract:
  We present a computational model to study the spatiotemporal dynamics of the
epidermis homeostasis under normal and pathological conditions. The model
consists of a population kinetics model of the central transition pathway of
keratinocyte proliferation, differentiation and loss and an agent-based model
that propagates cell movements and generates the stratified epidermis. The
model recapitulates observed homeostatic cell density distribution, the
epidermal turnover time and the multilayered tissue structure. We extend the
model to study the onset, recurrence and phototherapy-induced remission of
psoriasis. The model considers the psoriasis as a parallel homeostasis of
normal and psoriatic keratinocytes originated from a shared stem-cell niche
environment and predicts two homeostatic modes of the psoriasis: a disease mode
and a quiescent mode. Interconversion between the two modes can be controlled
by interactions between psoriatic stem cells and the immune system and by the
normal and psoriatic stem cells competing for growth niches. The prediction of
a quiescent state potentially explains the efficacy of the multi-episode UVB
irradiation therapy and recurrence of psoriasis plaques, which can further
guide designs of therapeutics that specifically target the immune system and/or
the keratinocytes.


title: Some Maximal Commutative Subrings of M_n(D)

abstract:
  We answer a question of Weibel and show that maximal commutative subgrings of
Artinian semisimple rings are direct products of local rings.


title:
Quantum Structure of Field Theory and Standard Model Based on
  Infinity-free Loop Regularization/Renormalization

abstract:
  To understand better the quantum structure of field theory and standard model
in particle physics, it is necessary to investigate carefully the divergence
structure in quantum field theories (QFTs) and work out a consistent framework
to avoid infinities. The divergence has got us into trouble since developing
quantum electrodynamics in 1930s, its treatment via the renormalization scheme
is satisfied not by all physicists, like Dirac and Feynman who have made
serious criticisms. The renormalization group analysis reveals that QFTs can in
general be defined fundamentally with the meaningful energy scale that has some
physical significance, which motivates us to develop a new symmetry-preserving
and infinity-free regularization scheme called loop regularization (LORE). A
simple regularization prescription in LORE is realized based on a manifest
postulation that a loop divergence with a power counting dimension larger than
or equal to the space-time dimension must vanish. The LORE method is achieved
without modifying original theory and leads the divergent Feynman loop
integrals well-defined to maintain the divergence structure and meanwhile
preserve basic symmetries of original theory. The crucial point in LORE is the
presence of two intrinsic energy scales which play the roles of ultraviolet
cut-off $M_c$ and infrared cut-off $\mu_s$ to avoid infinities. The key concept
in LORE is the introduction of irreducible loop integrals (ILIs) on which the
regularization prescription acts, which leads to a set of gauge invariance
consistency conditions between the regularized tensor-type and scalar-type
ILIs. The evaluation of ILIs with ultraviolet-divergence-preserving (UVDP)
parametrization naturally leads to Bjorken-Drell's analogy between Feynman
diagrams and electric circuits. The LORE method has been shown to be applicable
to both underlying and effective QFTs.


title:
Strong impact of the eddy-current shielding on ferromagnetic resonance
  response of sub-skin-depth-thick conducting magnetic multilayers

abstract:
  Exchange-coupled nonmagnetic (NM) and ferromagnetic (FM) conducting
multilayers are crucial for microwave spintronic devices of the future. We
demonstrate, experimentally and theoretically, that in broadband measurements
of ferromagnetic resonance (FMR) 10-70 nm-thick permalloy (Py) layers are
shielded from the dynamic magnetic field of the microstrip line by eddy
currents circulating in the NM capping layers, which strongly diminishes the
amplitude of magnetisation precession in the FM material. Our findings have
direct implications for designing broadband FMR and measurements of spin
current injection through interfaces realised by placing a conducting
multilayer above a microwave microstrip line. We show that the eddy-current
shielding is very strong at high microwave frequencies (30 GHz) even when the
thickness of the NM capping layer is <5 nm, which is well below the microwave
skin depth for Au, Cu, Ta, Pd, Pt and other NM metals technologically important
for spintronics.


title:
Stokes' theorem, gauge symmetry and the time-dependent Aharonov-Bohm
  effect

abstract:
  Stokes' theorem is investigated in the context of the time-dependent
Aharonov-Bohm effect -- the two-slit quantum interference experiment with a
time varying solenoid between the slits. The time varying solenoid produces an
electric field which leads to an additional phase shift which is found to
exactly cancel the time-dependent part of the usual magnetic Aharonov-Bohm
phase shift. This electric field arises from a combination of a non-single
valued scalar potential and/or a 3-vector potential. The gauge transformation
which leads to the scalar and 3-vector potentials for the electric field is
non-single valued. This feature is connected with the non-simply connected
topology of the Aharonov-Bohm set-up. The non-single valued nature of the gauge
transformation function has interesting consequences for the 4-dimensional
Stokes' theorem for the time-dependent Aharonov-Bohm effect. An experimental
test of these conclusions is proposed.


title: Exact Hausdorff Measure of Certain Non-Self-Similar Cantor Sets

abstract:
  We establish a formula yielding the Hausdorff measure for a class of
non-self-similar Cantor sets in terms of the canonical covers of the Cantor
set.


title: An HDG method for linear elasticity with strong symmetric stresses

abstract:
  This paper presents a new hybridizable discontinuous Galerkin (HDG) method
for linear elasticity on general polyhedral meshes, based on a strong symmetric
stress formulation. The key feature of this new HDG method is the use of a
special form of the numerical trace of the stresses, which makes the error
analysis different from the projection-based error analyzes used for most other
HDG methods. For arbitrary polyhedral elements, we approximate the stress by
using polynomials of degree k>=1 and the displacement by using polynomials of
degree k+1. In contrast, to approximate the numerical trace of the displacement
on the faces, we use polynomials of degree k only. This allows for a very
efficient implementation of the method, since the numerical trace of the
displacement is the only globally-coupled unknown, but does not degrade the
convergence properties of the method. Indeed, we prove optimal orders of
convergence for both the stresses and displacements on the elements. In the
almost incompressible case, we show the error of the stress is also optimal in
the standard L2-norm. These optimal results are possible thanks to a special
superconvergence property of the numerical traces of the displacement, and
thanks to the use of a crucial elementwise Korn's inequality. Several numerical
results are presented to support our theoretical findings in the end.


title:
Crumpled-to-tubule transition and shape transformations of a model of
  self-avoiding spherical meshwork

abstract:
  This paper analyzes a new self-avoiding (SA) meshwork model using the
canonical Monte Carlo simulation technique on lattices that consist of
connection-fixed triangles. The Hamiltonian of this model includes a
self-avoiding potential and a pressure term. The model identifies a
crumpled-to-tubule (CT) transition between the crumpled and tubular phases.
This is a second-order transition, which occurs when the pressure difference
between the inner and outer sides of the surface is close to zero. We obtain
the Flory swelling exponents $\nu_{{\rm R}^2}(=\!D_f/2)$ and $\bar{\nu}_{\rm
v}$ corresponding to the mean square radius of gyration $R_g^2$ and enclosed
volume $V$, where $D_f$ is the fractal dimension. The analysis shows that
$\bar{\nu}_{\rm v}$ at the transition is almost identical to the one of the
smooth phase of previously reported SA model which has no crumpled phase.


title: A short extension of two of Spira's results

abstract:
  Two inequalities concerning the symmetry of the zeta-function and the
Ramanujan $\tau$-function are improved through the use of some elementary
considerations.


title:
Electric potential profile of a spherical soft particle with a charged
  core

abstract:
  The electrostatic potential profile of a spherical soft particle is derived
by solving the Poisson-Boltzmann equations on a spherical system both
numerically and analytically. The soft particle is assumed to consist of an
ion-permeable charged outer layer and a non-permeable charged core with
constant charged density. The contribution of the core to the potential profile
is calculated for different charges and dielectric constants. Our results show
that the charged core heavily influences the local potential within the soft
particle. In contrast, the potential distribution outside the particle in the
salt solution is found to be weakly dependent on the core features. These
findings are consistent with previous experiments showing the minor impact of
the core of the MS2 virus on its overall electrical properties. Our studies
also indicate that while a change in temperature from 290 K to 310 K only
slightly varies the potential, the ionic strength in the range of 1-600 mM has
a significant effect on the potential profile. Our studies would provide good
understanding for experimental research in the field of biophysics and
nanomedicine.


title:
Don't sit on the fence: A static analysis approach to automatic fence
  insertion

abstract:
  Modern architectures rely on memory fences to prevent undesired weakenings of
memory consistency. As the fences' semantics may be subtle, the automation of
their placement is highly desirable. But precise methods for restoring
consistency do not scale to deployed systems code. We choose to trade some
precision for genuine scalability: our technique is suitable for large code
bases. We implement it in our new musketeer tool, and detail experiments on
more than 350 executables of packages found in Debian Linux 7.1, e.g. memcached
(about 10000 LoC).


title:
Rigorous asymptotic and moment-preserving diffusion approximations for
  generalized linear Boltzmann transport in arbitrary dimension

abstract:
  We derive new diffusion solutions to the monoenergetic generalized linear
Boltzmann transport equation (GLBE) for the stationary collision density and
scalar flux about an isotropic point source in an infinite $d$-dimensional
absorbing medium with isotropic scattering. We consider both classical
transport theory with exponentially-distributed free paths in arbitrary
dimensions as well as a number of non-classical transport theories
(non-exponential random flights) that describe a broader class of transport
processes within partially-correlated random media. New rigorous asymptotic
diffusion approximations are derived where possible. We also generalize
Grosjean's moment-preserving approach of separating the first (or uncollided)
distribution from the collided portion and approximating only the latter using
diffusion. We find that for any spatial dimension and for many free-path
distributions Grosjean's approach produces compact, analytic approximations
that are, overall, more accurate for high absorption and for small
source-detector separations than either $P_1$ diffusion or rigorous asymptotic
diffusion. These diffusion-based approximations are exact in the first two even
spatial moments, which we derive explicitly for various non-classical transport
types. We also discuss connections between the random-flight-theory derivation
of the Green's function and the discrete spectrum of the transport operator and
report some new observations regarding the discrete eigenvalues of the
transport operator for general dimensions and free-path distributions.


title: Fast Subspace Approximation via Greedy Least-Squares

abstract:
  In this note, we develop fast and deterministic dimensionality reduction
techniques for a family of subspace approximation problems. Let $P\subset
\mathbbm{R}^N$ be a given set of $M$ points. The techniques developed herein
find an $O(n \log M)$-dimensional subspace that is guaranteed to always contain
a near-best fit $n$-dimensional hyperplane $\mathcal{H}$ for $P$ with respect
to the cumulative projection error $(\sum_{{\bf x} \in P} \| {\bf x} -
\Pi_\mathcal{H} {\bf x} \|^p_2)^{1/p}$, for any chosen $p > 2$. The
deterministic algorithm runs in $\tilde{O} (MN^2)$-time, and can be randomized
to run in only $\tilde{O} (MNn)$-time while maintaining its error guarantees
with high probability. In the case $p = \infty$ the dimensionality reduction
techniques can be combined with efficient algorithms for computing the John
ellipsoid of a data set in order to produce an $n$-dimensional subspace whose
maximum $\ell_2$-distance to any point in the convex hull of $P$ is minimized.
The resulting algorithm remains $\tilde{O} (MNn)$-time. In addition, the
dimensionality reduction techniques developed herein can also be combined with
other existing subspace approximation algorithms for $2 < p \leq \infty$ -
including more accurate algorithms based on convex programming relaxations - in
order to reduce their runtimes.


title: Exponential improvement in precision for simulating sparse Hamiltonians

abstract:
  We provide a quantum algorithm for simulating the dynamics of sparse
Hamiltonians with complexity sublogarithmic in the inverse error, an
exponential improvement over previous methods. Specifically, we show that a
$d$-sparse Hamiltonian $H$ acting on $n$ qubits can be simulated for time $t$
with precision $\epsilon$ using $O\big(\tau
\frac{\log(\tau/\epsilon)}{\log\log(\tau/\epsilon)}\big)$ queries and
$O\big(\tau \frac{\log^2(\tau/\epsilon)}{\log\log(\tau/\epsilon)}n\big)$
additional 2-qubit gates, where $\tau = d^2 \|{H}\|_{\max} t$. Unlike previous
approaches based on product formulas, the query complexity is independent of
the number of qubits acted on, and for time-varying Hamiltonians, the gate
complexity is logarithmic in the norm of the derivative of the Hamiltonian. Our
algorithm is based on a significantly improved simulation of the continuous-
and fractional-query models using discrete quantum queries, showing that the
former models are not much more powerful than the discrete model even for very
small error. We also simplify the analysis of this conversion, avoiding the
need for a complex fault correction procedure. Our simplification relies on a
new form of "oblivious amplitude amplification" that can be applied even though
the reflection about the input state is unavailable. Finally, we prove new
lower bounds showing that our algorithms are optimal as a function of the
error.


title:
Better buffers for patches in macroscale simulation of systems with
  microscale randomness

abstract:
  We consider one dimensional lattice diffusion model on a microscale grid with
many discrete diffusivity values which repeat periodicially. Computer algebra
explores how the dynamics of small coupled `patches' predict the slow emergent
macroscale dynamics. We optimise the geometry and coupling of patches by
comparing the macroscale predictions of the patch solutions with the macroscale
solution on the infinite domain, which is derived for a general diffusivity
period. The results indicate that patch dynamics is a viable method for
numerical macroscale modelling of microscale systems with fine scale roughness.
Moreover, the minimal error on the macroscale is generally obtained by coupling
patches via `buffers' that are as large as half of each patch.


title: Flash ADC data processing with correlation coefficients

abstract:
  The large growth of flash ADC techniques for processing signals, especially
in applications of streaming data, raises issues such as data flow through an
acquisition system, long-term storage, and greater complexity in data analysis.
In addition, experiments that push the limits of sensitivity need to
distinguish legitimate signals from noise. The use of correlation coefficients
is examined to address these issues. They are found to be quite successful well
into the noise region. The methods can also be extended to Field Programmable
Gate Array modules for compressing the data flow and greatly enhancing the
event rate capabilities.


title:
1st or 2nd; the order of finite temperature phase transition of Nf=2 QCD
  from effective theory analysis

abstract:
  In the previous work, we have shown that the SU(2) chiral symmetry recovered
above the critical temperature gives a strong constraint on the Dirac
eigenvalue spectrum and this constraint is strong enough for a set of anomalous
U(1) chiral symmetry breaking operators to vanish in the thermodynamical and
chiral limits. We use this condition as an input and impose a constraint on the
Landau low energy effective theory of QCD. The only constraint we can set is
that the mass splitting term between the pion and eta meson should vanish. All
the singlet/non-singlet scalar/pseudo-scalar mesons contribute to the effective
theory. We evaluate the renormalization group $\beta$-function for the
effective theory using the $\epsilon$-expansion at one loop level, but find no
stable infra-red fixed point except for the trivial Gaussian one. The chiral
phase transition seems to be of first order.


title:
Synthesis and optical properties of large-scale single-crystalline
  two-dimensional semiconductor WS2 monolayer from chemical vapor deposition

abstract:
  Two-dimensional (2D) transition metal dichalcogenides (TMDs), especially MoS2
and WS2 recently attract extensive attentions due to their rich physics and
great potential applications. Superior to graphene, MS2 (M = Mo/W) monolayers
have a native direct energy gap in visible frequency range. This promises great
future of MS2 for optoelectronics. To exploit properties and further develop
more applications, producing large-scale single crystals of MS2 by a facile
method is highly demanded. Here, we report the synthesis of large-scale
triangular single crystals of WS2 monolayer from a chemical vapor deposition
process and systematic optical studies of such WS2 monolayers. The observations
of high yield of light emission and valley-selective circular dichroism
experimentally evidence the high optical quality of the WS2 monolayers. This
work paves the road to fabricate large-scale single crystalline 2D
semiconductors and study their fundamentals. It must be very meaningful for
exploiting great potentials of WS2 for future optoelectronics.


title: Conformal Pomeron and Odderon in Strong Coupling

abstract:
  We discuss how exact conformal invariance in the strong coupling leads
naturally through AdS/CFT correspondence to a systematic expansion for the
Pomeron and Odderon intercepts in power of $\lambda^{-1/2}$, with
$\lambda=g^2N_c$ the 't Hooft coupling. We also point out the importance of
confinement for a realistic treatment of DIS in the HERA energy range.


title: Null fluid collapse in brane world models

abstract:
  The brane world description of our universe entails a large extra dimension
and a fundamental scale of gravity that may be lower than the Planck scale by
several orders of magnitude. An interesting consequence of this scenario occurs
in the nature of spherically-symmetric vacuum solutions to the brane
gravitational field equations, which often have properties quite distinct from
the standard black hole solutions of general relativity. In this paper, the
spherically-symmetric collapse on the brane world of four types of null fluid,
governed by the barotropic, polytropic, strange quark "bag" model and Hagedorn
equations of state, is investigated. In each case, we solve the approximate
gravitational field equations, obtained in the high density limit, determine
the equation which governs the formation of apparent horizons and investigate
the conditions for the formation of naked singularities. Though, naively, one
would expect the increased effective energy density on the brane to favor the
formation of black holes over naked singularities, we find that, for the types
of fluid considered, this is not the case. However, the black hole solutions
differ substantially from their general-relativistic counterparts and brane
world corrections often play a role analogous to charge in general relativity.
As a possible astrophysical application of this work, the possibility that
energy emission from a Hagedorn fluid collapsing to form a naked singularity
may be a source of GRBs in the brane world is also considered.


title: Intermittent Communication

abstract:
  We formulate a model for intermittent communication that can capture bursty
transmissions or a sporadically available channel, where in either case the
receiver does not know a priori when the transmissions will occur. Focusing on
the point-to-point case, we develop a decoding structure, decoding from pattern
detection, and its achievable rate for such communication scenarios. Decoding
from pattern detection first detects the locations of codeword symbols and then
uses them to decode. We introduce the concept of partial divergence and study
some of its properties in order to obtain stronger achievability results. As
the system becomes more intermittent, the achievable rates decrease due to the
additional uncertainty about the positions of the codeword symbols at the
decoder. Additionally, we provide upper bounds on the capacity of binary
noiseless intermittent communication with the help of a genie-aided encoder and
decoder. The upper bounds imply a tradeoff between the capacity and the
intermittency rate of the communication system, even if the receive window
scales linearly with the codeword length.


title: Derangements in Cosets of Primitive Permutation Groups

abstract:
  Motivated by questions arising in connection with branched coverings of
connected smooth projective curves over finite fields, we study the proportion
of fixed point free elements (derangements) in cosets of normal subgroups of
primitive permutations groups. Using the Aschbacher-O'Nan-Scott theorem for
primitive groups to partition the problem, we provide complete answers for
affine groups and groups which contain a regular normal nonabelian subgroup.


title:
ABC-SG: A New Artificial Bee Colony Algorithm-Based Distance of
  Sequential Data Using Sigma Grams

abstract:
  The problem of similarity search is one of the main problems in computer
science. This problem has many applications in text-retrieval, web search,
computational biology, bioinformatics and others. Similarity between two data
objects can be depicted using a similarity measure or a distance metric. There
are numerous distance metrics in the literature, some are used for a particular
data type, and others are more general. In this paper we present a new distance
metric for sequential data which is based on the sum of n-grams. The novelty of
our distance is that these n-grams are weighted using artificial bee colony; a
recent optimization algorithm based on the collective intelligence of a swarm
of bees on their search for nectar. This algorithm has been used in optimizing
a large number of numerical problems. We validate the new distance
experimentally.


title:
The Size-distribution of Scattered Disk TNOs from that of JFCs between
  0.2 and 15km effective radius

abstract:
  We investigate the size-frequency distribution of Jupiter Family comets to
determine whether they are primordial accreted objects or collisional
fragments. We develop a list of effective radii and their uncertainties for 161
active JFCs and compute the observed size-frequency distribution using a
Probability Index technique. The radii range from 0.2 to 15.4 km. This is then
corrected for the effects of observational selection using a model published
earlier by Meech et al.(2004). We estimate that the total number of active JFCs
between 0.2 and 15.4 km is approximately 2300.The active JFC size-frequency
distribution, over the range from 0.6 to 10 km where it is best defined, is
found to be closer to an exponential distribution in character than a
power-law. We then develop a statistical model, based on the assumption of a
steady state, for converting the distribution of active JFCs to the SFD of the
source population among the TNOs. The model includes the effects of
devolatization (that produces a large sub-class of defunct nuclei) and
surficial mass-loss. Comparison with available TNO observations shows that to
simultaneously attain continuity with the data on objects in the hot TNO
population (Fuentes et al,2010), satisfy constraints on the number of TNOs set
by the occultation detections of Schlichting et al.(2012), and to remain within
upper limits set by the Taiwanese-American Occultation Survey (TAOS; Zhang et
al,2013) the total JFC population must contain a large fraction of small
defunct nuclei. The effective power-law index of the inferred TNO differential
SFD between 1 and 10 km is -4.5 +/- 0.5 indicating a population in this range
that is not in fully relaxed collisional equilibrium. We conclude that the
cometary nuclei visited by spacecraft and many JFCs are primordial accreted
objects relatively unaffected by collisional evolution.


title:
Light Trapping in Thin Film Disordered Nanohole Patterns: Effects of
  Oblique Incidence and Intrinsic Absorption

abstract:
  Finite-difference time-domain method is employed to investigate the optical
properties of semiconductor thin films patterned with circular holes. The
presence of holes enhances the coupling of the incident plane wave with the
thin film and greatly enhances the absorption performance. For a typical 100 nm
thin film, the optimal hole pattern is achieved when the hole radius is 180 nm
and volume fraction is about $30\%$. Disorderness can alter the absorption
spectra and has an impact on the broadband absorption performance. The
non-uniform radius of holes can slightly broaden the absorption peaks and
enhance the integrated absorption. Random hole position can completely change
the shape of the absorption spectra and the averaged integrated absorption
efficiency is slightly smaller than the optimized ordered nanohole pattern.
Compared to random positioned nanoholes or ordered nanohole, amorphous
arrangement of nanoholes will result in a much better absorption performance.
However, it is also found that the absorption enhancement of amorphous pattern
over an ordered pattern is weak when the incident angle departures from normal
or when the intrinsic material absorption is strong.


title:
Quantum Fisher information as signature of superradiant quantum phase
  transition

abstract:
  The single-mode Dicke model is well-known to undergo a quantum phase
transition from the so-called normal phase to the supperradiant phase
(hereinafter called the "superradiant quantum phase transition"). Normally,
quantum phase transitions are closely related to the critical behavior of
quantities such as entanglement, quantum fluctuations, and fidelity. In this
paper, we study quantum Fisher information (QFI) of the field mode and that of
the atoms in the ground state of the Dicke Hamiltonian. For finite and large
enough number of atoms, our numerical results show that near the critical
atom-field coupling, the QFIs of the atomic and the field subsystems can
surpass the classical limits, due to the appearance of nonclassical squeezed
states. As the coupling increases far beyond the critical point, the two
subsystems are in highly mixed states, which degrade the QFI and hence the
ultimate phase sensitivity. In the thermodynamic limit, we present analytical
results of the QFIs and their relationships with the reduced variances. For
each subsystem, we find that there is a singularity in the derivative of the
QFI at the critical point, a clear signature of quantum criticality in the
Dicke model.

categories: quant-ph cond-mat.quant-gas physics.atom-ph physics.data-an physics.optics


title: Normality degrees of finite groups

abstract:
  In this paper we introduce and study the concept of normality degree of a
finite group $G$. This quantity measures the probability of a random subgroup
of $G$ to be normal. Explicit formulas are obtained for some particular classes
of finite groups. Several limits of normality degrees are also computed.


title: A generalization of the Euler's totient function

abstract:
  The main goal of this paper is to provide a group theoretical generalization
of the well-known Euler's totient function. This determines an interesting
class of finite groups.


title:
On the number of diamonds in the subgroup lattice of a finite abelian
  group

abstract:
  The main goal of the current paper is to determine the total number of
diamonds in the subgroup lattice of a finite abelian group. This counting
problem is reduced to finite $p$-groups. Explicit formulas are obtained in some
particular cases.


title:
Modeling the Field Control of the Surface Electroclinic Effect near
  Continuous and First Order Smectic-A*-Smectic-C* Transitions

abstract:
  We present and analyze a model for the combination of bulk and surface
electroclinic effects in the smectic-A* (Sm-A) phase near a Sm-A*--Sm-C*
transition. As part of our analysis we calculate the dependence of the surface
tilt on external electric field and show that it can be eliminated, or even
reversed from its zero-field value. This is in good agreement with previous
experimental work on a system (W415) with a continuous Sm-A*--Sm-C* transition.
We also analyze, for the first time, the combination of bulk and surface
electroclinic effects in systems with a first order Sm-A*--Sm-C* transition.
The variation of surface tilt with electric field in this case is much more
dramatic, with discontinuities and hysteresis. Near each type of Sm-A*--Sm-C*
transition we obtain the temperature dependence of the field required to
eliminate surface tilt. Additionally, we analyze the effect of varying the
system's enantiomeric excess, showing that it strongly affects the field
dependence of surface tilt, in particular, near a first order Sm-A*--Sm-C*
transition. In this case, increasing enantiomeric excess can change the field
dependence of surface tilt from continuous to discontinuous. Our model also
allows us to calculate the variation of layer spacing in going from surface to
bulk, which in turn allows us to estimate the strain resulting from the
difference between the surface and bulk layer spacing. We show that for certain
ranges of applied electric field, this strain can result in layer buckling
which reduces the overall quality of the liquid crystal cell. For de Vries
materials, with small tilt-induced change in layer spacing, the induced strain
for a given surface tilt should be smaller. However, we argue that this may be
offset by the fact that de Vries materials, which typically have Sm-A*--Sm-C*
transitions near a tricritical point, will generally have larger surface tilt.


title: Computing in Operations Research using Julia

abstract:
  The state of numerical computing is currently characterized by a divide
between highly efficient yet typically cumbersome low-level languages such as
C, C++, and Fortran and highly expressive yet typically slow high-level
languages such as Python and MATLAB. This paper explores how Julia, a modern
programming language for numerical computing which claims to bridge this divide
by incorporating recent advances in language and compiler design (such as
just-in-time compilation), can be used for implementing software and algorithms
fundamental to the field of operations research, with a focus on mathematical
optimization. In particular, we demonstrate algebraic modeling for linear and
nonlinear optimization and a partial implementation of a practical simplex
code. Extensive cross-language benchmarks suggest that Julia is capable of
obtaining state-of-the-art performance.


title:
Finite temperature Casimir effect for massive scalars in a magnetic
  field

abstract:
  The finite temperature Casimir effect for a charged, massive scalar field
confined between very large, perfectly conducting parallel plates is studied
using the zeta function regularization technique. The scalar field satisfies
Dirichlet boundary conditions at the plates and a magnetic field perpendicular
to the plates is present. Four equivalent expressions for the zeta function are
obtained, which are exact to all orders in the magnetic field strength,
temperature, scalar field mass, and plate distance. The zeta function is used
to calculate the Helmholtz free energy of the scalar field and the Casimir
pressure on the plates, in the case of high temperature, small plate distance,
strong magnetic field and large scalar mass. In all cases, simple analytic
expressions of the zeta function, free energy and pressure are obtained, which
are very accurate and valid for practically all values of temperature, plate
distance, magnetic field and mass.


title:
On the limit of extreme eigenvalues of large dimensional random
  quaternion matrices

abstract:
  Since E.P.Wigner (1958) established his famous semicircle law, lots of
attention has been paid by physicists, probabilists and statisticians to study
the asymptotic properties of the largest eigenvalues for random matrices. Bai
and Yin (1988) obtained the necessary and sufficient conditions for the strong
convergence of the extreme eigenvalues of a Wigner matrix. In this paper, we
consider the case of quaternion self-dual Hermitian matrices. We prove the
necessary and sufficient conditions for the strong convergence of extreme
eigenvalues of quaternion self-dual Hermitian matrices corresponding to the
Wigner case.


title:
Folding model analysis of the inelastic $\alpha+^{12}$C scattering at
  medium energies, and the isoscalar transition strengths of the cluster states
  of $^{12}$C

abstract:
  The complex optical potential and inelastic form factor given by the folding
model for the $\alpha+^{12}$C scattering are used to calculate the
($\alpha,\alpha'$) cross sections for the known isoscalar states of $^{12}$C in
an elaborate coupled channel approach. The strengths of the form factors for
these states are then fine tuned against the ($\alpha,\alpha'$) data to deduce
the corresponding $E\lambda$ transition strengths. A significant $E2$
transition strength has been obtained for the $2^+_2$ state from the present
analysis of the ($\alpha,\alpha'$) data measured at $E_\alpha=240$ and 386 MeV.
The $E\lambda$ transition strengths of the $0^+_2,\ 3^-_1,\ 0^+_3,$ and $1^-_1$
states were also carefully deduced, and some difference from the results of
earlier analyses has been found and qualitatively understood.


title:
Electrically Tunable Excitonic Light Emitting Diodes based on Monolayer
  WSe2 p-n Junctions

abstract:
  Light-emitting diodes are of importance for lighting, displays, optical
interconnects, logic and sensors. Hence the development of new systems that
allow improvements in their efficiency, spectral properties, compactness and
integrability could have significant ramifications. Monolayer transition metal
dichalcogenides have recently emerged as interesting candidates for
optoelectronic applications due to their unique optical properties.
Electroluminescence has already been observed from monolayer MoS2 devices.
However, the electroluminescence efficiency was low and the linewidth broad due
both to the poor optical quality of MoS2 and to ineffective contacts. Here, we
report electroluminescence from lateral p-n junctions in monolayer WSe2 induced
electrostatically using a thin boron nitride support as a dielectric layer with
multiple metal gates beneath. This structure allows effective injection of
electrons and holes, and combined with the high optical quality of WSe2 it
yields bright electroluminescence with 1000 times smaller injection current and
10 times smaller linewidth than in MoS2. Furthermore, by increasing the
injection bias we can tune the electroluminescence between regimes of
impurity-bound, charged, and neutral excitons. This system has the required
ingredients for new kinds of optoelectronic devices such as spin- and
valley-polarized light-emitting diodes, on-chip lasers, and two-dimensional
electro-optic modulators.


title:
Security flaw of counterfactual quantum cryptography in practical
  setting

abstract:
  Recently, counterfactual quantum cryptography proposed by T. G. Noh [Phys.
Rev. Lett. 103, 230501 (2009)] becomes an interesting direction in quantum
cryptography, and has been realized by some researchers (such as Y. Liu et al's
[Phys. Rev. Lett. 109, 030501 (2012)]). However, we find out that it is
insecure in practical high lossy channel setting. We analyze the secret key
rates in lossy channel under a polarization-splitting-measurement attack.
Analysis indicates that the protocol is insecure when the loss rate of the
one-way channel exceeds $50%$.


title: Initial Ranging for Prioritized Network Entry in IEEE 802.16 Network

abstract:
  Prioritized network entry is desirable for establishing preferential network
connectivity for the higher priority users when different priority users exist
over a given network. In line with such desirability, we propose a simple but
efficient priority differentiated initial ranging mechanism considering an
Orthogonal Frequency Division Multiple Access (OFDMA) based IEEE 802.16
network. In the proposed mechanism, we introduce an approach that integrates an
explicit CDMA-ranging code reservation scheme with a Ranging Slot Selection
Window (RSSW) differentiation scheme. Simulation results are provided to
characterize the performance of the proposed mechanism.


title: Observational tests of the picture of disk accretion

abstract:
  In this chapter, I present a summary of observational tests of the basic
picture of disk accretion. An emphasis is placed on tests relevant to black
holes, but many of the fundamental results are drawn from studies of other
classes of systems. Evidence is discussed for the basic structures of accretion
flows. The cases of systems with and without accretion disks are discussed, as
is the evidence that disks actually form. Also discussed are the hot spots
where accretion streams impact the disks, and the boundary layers in the inner
parts of systems where the accretors are not black holes. The nature of slow,
large amplitude variability is discussed. It is shown that some of the key
predictions of the classical thermal-viscous ionization instability model for
producing outbursts are in excellent agreement with observational results. It
is also show that there are systems whose outbursts are extremely difficult to
explain without invoking variations in the rate of mass transfer from the donor
star into the outer accretion disk, or tidally induced variations in the mass
transfer rates. Finally, I briefly discuss recent quasar microlensing
measurements which give truly independent constraints on the inner accretion
geometry around black holes.


title: Flat connections and resonance varieties: from rank one to higher ranks

abstract:
  Given a finitely-generated group $\pi$ and a linear algebraic group $G$, the
representation variety Hom$(\pi,G)$ has a natural filtration by the
characteristic varieties associated to a rational representation of $G$. Its
algebraic counterpart, the space of $\mathfrak{g}$-valued flat connections on a
commutative, differential graded algebra $(A,d)$ admits a filtration by the
resonance varieties associated to a representation of $\mathfrak{g}$. We
establish here a number of results concerning the structure and qualitative
properties of these embedded resonance varieties, with particular attention to
the case when the rank 1 resonance variety decomposes as a finite union of
linear subspaces. The general theory is illustrated in detail in the case when
$\pi$ is either an Artin group, or the fundamental group of a smooth,
quasi-projective variety.


title: A Variational Principle for Discrete Integrable Systems

abstract:
  For integrable systems in the sense of multidimensional consistency (MDC) we
can consider the Lagrangian as a form, which is closed on solutions of the
equations of motion. For 2-dimensional systems, described by partial difference
equations with two independent variables, MDC allows us to define an action on
arbitrary 2-dimensional surfaces embedded in a higher dimensional space of
independent variables, where the action is not only a functional of the field
variables but also the choice of surface. It is then natural to propose that
the system should be derived from a variational principle which includes not
only variations with respect to the dependent variables, but also with respect
to variations of the surface in the space of independent variables. Here we
derive the resulting system of generalized Euler-Lagrange equations arising
from that principle. We treat the case where the equations are 2 dimensional
(but which due to MDC can be consistently embedded in higher-dimensional
space), and show that they can be integrated to yield relations of
quadrilateral type. We also derive the extended set of Euler-Lagrange equations
for 3-dimensional systems, i.e., those for equations with 3 independent
variables. The emerging point of view from this study is that the variational
principle can be considered as the set of equations not only encoding the
equations of motion but as the defining equations for the Lagrangians
themselves.


title:
A background simulation method for cosmogenic nuclides inside HPGe
  detectors for rare event experiments

abstract:
  Cosmogenic nuclides inside germanium detectors contribute background noise
spectra quite different from ordinary external sources. We propose and discuss
a nuclide decay and level transition model based on graph theory to understand
the background contribution of the decay of cosmogenic nuclides inside a
germanium crystal. In this work, not only was the level transition process, but
the detector response time was also taken into consideration to decide whether
or not to apply coincidence summing-up. We simulated the background spectrum of
the internal cosmogenic nuclides in a germanium detector, and found some unique
phenomena caused by the coincidence summing-up effect in the simulated
spectrum. Thus, the background spectrum of each cosmogenic nuclide can be
quantitatively obtained.


title:
Pressure of Degenerate and Relativistic electrons in a superhigh
  magnetic field

abstract:
  Based on our previous work, we deduce a general formula for pressure of
degenerate and relativistic electrons,Pe, which is suitable for superhigh
magnetic fields, discuss the quantization of Landau levels of electrons, and
consider the quantum electrodynam-ic(QED) effects on the equations of states
(EOSs) for different matter systems. The main conclusions are as follows:Pe is
related to the magnetic field B, matter density ?, and electron fraction Ye ;
the stronger the magnetic field, the higher the electron pressure becomes; the
high electron pressure could be caused by high Fermi energy of electrons in a
superhigh magnetic field; compared with a common radio pulsar, a magnetar could
be a more compact oblate spheroid-like deformed neutron star due to the
anisotropic total pressure; and an increase in the maximum mass of a magnetar
is expected because of the positive contribution of the magnetic field energy
to the EOS of the star.


title:
Constraints on a $\phi$CDM model from strong gravitational lensing and
  updated Hubble parameter measurements

abstract:
  We constrain the scalar field dark energy model with an inverse power-law
potential, i.e., $V(\phi)\propto {\phi}^{-\alpha}$ ($\alpha>0$), from a set of
recent cosmological observations by compiling an updated sample of Hubble
parameter measurements including 30 independent data points. Our results show
that the constraining power of the updated sample of $H(z)$ data with the HST
prior on $H_0$ is stronger than those of the SCP Union2 and Union2.1
compilations. A recent sample of strong gravitational lensing systems is also
adopted to confine the model even though the results are not significant. A
joint analysis of the strong gravitational lensing data with the more
restrictive updated Hubble parameter measurements and the Type Ia supernovae
data from SCP Union2 indicates that the recent observations still can not
distinguish whether dark energy is a time-independent cosmological constant or
a time-varying dynamical component.


title: Energy Beamforming with One-Bit Feedback

abstract:
  Wireless energy transfer (WET) has attracted significant attention recently
for providing energy supplies wirelessly to electrical devices without the need
of wires or cables. Among different types of WET techniques, the radio
frequency (RF) signal enabled far-field WET is most practically appealing to
power energy constrained wireless networks in a broadcast manner. To overcome
the significant path loss over wireless channels, multi-antenna or
multiple-input multiple-output (MIMO) techniques have been proposed to enhance
the transmission efficiency and distance for RF-based WET. However, in order to
reap the large energy beamforming gain in MIMO WET, acquiring the channel state
information (CSI) at the energy transmitter (ET) is an essential task. This
task is particularly challenging for WET systems, since existing channel
training and feedback methods used for communication receivers may not be
implementable at the energy receiver (ER) due to its hardware limitation. To
tackle this problem, in this paper we consider a multiuser MIMO system for WET,
where a multiple-antenna ET broadcasts wireless energy to a group of
multiple-antenna ERs concurrently via transmit energy beamforming. By taking
into account the practical energy harvesting circuits at the ER, we propose a
new channel learning method that requires only one feedback bit from each ER to
the ET per feedback interval. The feedback bit indicates the increase or
decrease of the harvested energy by each ER between the present and previous
intervals, which can be measured without changing the existing hardware at the
ER. Based on such feedback information, the ET adjusts transmit beamforming in
different training intervals and at the same time obtains improved estimates of
the MIMO channels to ERs by applying a new approach termed analytic center
cutting plane method (ACCPM).


title: Bayesian machine learning via category theory

abstract:
  From the Bayesian perspective, the category of conditional probabilities (a
variant of the Kleisli category of the Giry monad, whose objects are measurable
spaces and arrows are Markov kernels) gives a nice framework for
conceptualization and analysis of many aspects of machine learning. Using
categorical methods, we construct models for parametric and nonparametric
Bayesian reasoning on function spaces, thus providing a basis for the
supervised learning problem. In particular, stochastic processes are arrows to
these function spaces which serve as prior probabilities. The resulting
inference maps can often be analytically constructed in this symmetric monoidal
weakly closed category. We also show how to view general stochastic processes
using functor categories and demonstrate the Kalman filter as an archetype for
the hidden Markov model.


title: Valuing Student Ideas Morally, Instrumentally, and Intellectually

abstract:
  The importance of valuing student ideas in science education stands on firm
empirical, theoretical, and moral grounds. However, the reasons for which one
might value student ideas are often not explicitly distinguished, even if
implicit distinctions are made in the literature. In this paper, I define and
distinguish between three ways of valuing student ideas: moral, instrumental,
and intellectual. I demonstrate that novice teachers in the Seattle Pacific
University (SPU) Learning Assistant (LA) Program instantiate all three ways of
valuing student ideas. Not only this, over the course of their participation in
the LA Program, novice teachers shift from foregrounding the moral and
instrumental value of student ideas toward highlighting their intellectual
value.


title: Asynchronous Convolutional-Coded Physical-Layer Network Coding

abstract:
  This paper investigates the decoding process of asynchronous
convolutional-coded physical-layer network coding (PNC) systems. Specifically,
we put forth a layered decoding framework for convolutional-coded PNC
consisting of three layers: symbol realignment layer, codeword realignment
layer, and joint channel-decoding network coding (Jt-CNC) decoding layer. Our
framework can deal with phase asynchrony and symbol arrival-time asynchrony
between the signals simultaneously transmitted by multiple sources. A salient
feature of this framework is that it can handle both fractional and integral
symbol offsets; previously proposed PNC decoding algorithms (e.g., XOR-CD and
reduced-state Viterbi algorithms) can only deal with fractional symbol offset.
Moreover, the Jt-CNC algorithm, based on belief propagation (BP), is
BER-optimal for synchronous PNC and near optimal for asynchronous PNC.
Extending beyond convolutional codes, we further generalize the Jt-CNC decoding
algorithm for all cyclic codes. Our simulation shows that Jt-CNC outperforms
the previously proposed XOR-CD algorithm and reduced-state Viterbi algorithm by
2dB for synchronous PNC. For phase-asynchronous PNC, Jt-CNC is 4dB better than
the other two algorithms. Importantly, for real wireless environment testing,
we have also implemented our decoding algorithm in a PNC system built on the
USRP software radio platform. Our experiment shows that the proposed Jt-CNC
decoder works well in practice.


title: Food Recommendation using Ontology and Heuristics

abstract:
  Recommender systems are needed to find food items of ones interest. We review
recommender systems and recommendation methods. We propose a food
personalization framework based on adaptive hypermedia. We extend Hermes
framework with food recommendation functionality. We combine TF-IDF term
extraction method with cosine similarity measure. Healthy heuristics and
standard food database are incorporated into the knowledgebase. Based on the
performed evaluation, we conclude that semantic recommender systems in general
outperform traditional recommenders systems with respect to accuracy,
precision, and recall, and that the proposed recommender has a better F-measure
than existing semantic recommenders.


title: Nucleon QCD sum rules in instanton medium

abstract:
  We try to find the grounds for the standard nucleon QCD sum rules, based on
more detailed description of QCD vacuum. We calculate the polarization operator
of the nucleon current in the instanton medium. The medium (QCD vacuum) is
assumed to be a composition of the small-size instantons and some long-wave
gluon fluctuations. We solve the corresponding QCD sum rules equations and
demonstrate that there is a solution with the value of the nucleon mass close
to the physical one if the fraction of the small size instantons contribution
w_s \approx 2/3.


title: Multi-Antenna Wireless Powered Communication with Energy Beamforming

abstract:
  The newly emerging wireless powered communication networks (WPCNs) have
recently drawn significant attention, where radio signals are used to power
wireless terminals for information transmission. In this paper, we study a WPCN
where one multi-antenna access point (AP) coordinates energy transfer and
information transfer to/from a set of single-antenna users. A
harvest-then-transmit protocol is assumed where the AP first broadcasts
wireless power to all users via energy beamforming in the downlink (DL), and
then the users send their independent information to the AP simultaneously in
the uplink (UL) using their harvested energy. To optimize the users' throughput
and yet guarantee their rate fairness, we maximize the minimum throughput among
all users by a joint design of the DL-UL time allocation, the DL energy
beamforming, and the UL transmit power allocation plus receive beamforming. We
solve this non-convex problem optimally by two steps. First, we fix the DL-UL
time allocation and obtain the optimal DL energy beamforming, UL power
allocation and receive beamforming to maximize the minimum
signal-to-interference-plus-noise ratio (SINR) of all users. This problem is
shown to be in general non-convex; however, we convert it equivalently to a
spectral radius minimization problem, which can be solved efficiently by
applying the alternating optimization based on the non-negative matrix theory.
Then, the optimal time allocation is found by a one-dimension search to
maximize the minimum rate of all users. Furthermore, two suboptimal designs of
lower complexity are proposed, and their throughput performance is compared
against that of the optimal solution.


title:
Isospin Symmetry Breaking and Octet Baryon Masses due to Their Mixing
  with Decuplet Baryons

abstract:
  We study the isospin symmetry breaking and mass splittings of the eight
lowest-lying baryons. We consider three kinds of baryon mass terms, including
the bare mass term, the electromagnetic terms and the spontaneous chiral
symmetry breaking terms. We include the mixing term between flavor-octet and
flavor-decuplet baryons. This assumes that the lowest-lying Sigma and Xi
baryons contain a few decuplet components and so are not purely flavor-octet.
We achieve a good fitting that the difference between every fitted mass and its
experimental value is less than 0.2 MeV.


title: Developer Experience: Concept and Definition

abstract:
  New ways of working such as globally distributed development or the
integration of self-motivated external developers into software ecosystems will
require a better and more comprehensive understanding of developers' feelings,
perceptions, motivations and identification with their tasks in their
respective project environments. User experience is a concept that captures how
persons feel about products, systems and services. It evolved from disciplines
such as interaction design and usability to a much richer scope that includes
feelings, motivations, and satisfaction. Similarly, developer experience could
be defined as a means for capturing how developers think and feel about their
activities within their working environments, with the assumption that an
improvement of the developer experience has positive impacts on characteristics
such as sustained team and project performance. This article motivates the
importance of developer experience, sketches related approaches from other
domains, proposes a definition of developer experience that is derived from
similar concepts in other domains, describes an ongoing empirical study to
better understand developer experience, and finally gives an outlook on planned
future research activities.


title:
The study and design of RF coupler for Chinese ADS HWR Superconducting
  Cavity

abstract:
  RF power coupler is a key component of the superconducting accelerating
system in Chinese ADS proton linac injector I, which is used to transmit 15kW
RF power from the power source to the superconducting HWR cavity. According to
the requirement of working frequency, power level, transmission capability and
cooling condition, the physics design of coupler has been finished, which
includes RF structure optimization, thermal simulation, thermal stress analysis
and so on. Based on this design, the prototype of HWR coupler has been
fabricated, and then has passed the high power test successfully.


title: The initial condition problems of damped quantum harmonic oscillator

abstract:
  We investigate the exact dynamics of the damped quantum harmonic oscillator
under the (un)correlated initial conditions. The master equation is generalized
to the cases of the arbitrary factorized state and/or Gaussian state. We show
that the variances of the factorized Gaussian state do not sensitively depend
on the initial oscillator-bath correlation, which however can remarkably affect
the mean values even at high temperature. We also illustrate that the
correlations among the factorized states still give rise to the initial dips
during the purity evolutions, which can be smoothed out by increasing the
amount of correlation to some extent. We finally study the effects of repeated
measurements on the time evolution of the damped oscillator analytically, which
are compared with the weak coupling results to indicate that they give rather
different transient behaviors even for an intermediate coupling.


title: Heavy and light meson wavefunctions

abstract:
  We present a short review on the properties of heavy and light mesons'
light-cone wavefunctions (LCWFs), and their distribution amplitudes (DAs). The
B meson LCWFs can be treated by taking the heavy quark limit ($m_b\to\infty$)
and by using the heavy quark effective theory. Furthermore, we propose a simple
model for the B meson WFs with 3-particle Fock states' contributions, whose
behaviors are controlled by two parameters $\bar\Lambda$ and $\delta$. Using
such model, the form factors $F^{B\to\pi}_{+,0,T}$ and $F^{B\to K}_{+,0,T}$ in
large recoil region are studied up to ${\cal O}(1/m_b^2)$ within the $k_T$
factorization approach. On the other hand, we adopt Brodsky-Huang-Lepage (BHL)
prescription for constructing the WFs of the lighter pseudoscalars as $\eta_c$,
D-meson, pion, kaon, $\eta^{(\prime)}$ and etc. Such BHL-like model can be
conveniently extended to construct the LCWFs for light scalar or vector mesons.
Within such model the longitudinal distributions of those WFs are basically
determined by a parameter $B$, whose value can be determined via a global fit
of experimental data.


title: The Mayan Long Count Calendar

abstract:
  The Maya were known for their astronomical proficiency. This is demonstrated
in the Mayan codices where ritual practices were related to astronomical
events/predictions. Whereas Mayan mathematics were based on a vigesimal system,
they used a different base when dealing with long periods of time, the Long
Count Calendar (LCC), composed of different Long Count Periods: the Tun of 360
days, the Katun of 7200 days and the Baktun of 144000 days. There were two
other calendars used in addition to the LCC: a civil year Haab' of 365 days and
a religious year Tzolk'in of 260 days. Another cycle was also in use: a
3276-day cycle (combination of the 819-day Kawil cycle and the 4
directions-colors). Based on the hypothesis that Mayan astronomers had a good
knowledge of naked-eye astronomy, we propose here an explanation of the origin
of the LCC, the Haab', the Tzolk'in and the 3276-day cycle. This study sheds
more light on the connection between arithmetic, astronomy and religion in Maya
civilization.


title:
Random Backward Iteration Algorithm for Julia sets of Rational
  Semigroups

abstract:
  We consider the dynamics of rational semigroups (semigroups of rational maps)
on the Riemann sphere. We provide proof that a random backward iteration
algorithm to draw the pictures of the Julia sets, previously proven to work in
the context of iteration of a rational map of degree two or more, extends to
finitely generated rational semigroups (of a certain type). We also provide
some consequences of this result.


title:
Precise predictions for $A_H q_-$ associated production in the littlest
  Higgs model with $T$ parity at the LHC

abstract:
  In the framework of the littlest Higgs model with $T$ parity, we present
complete calculations for the $A_H q_-$ $(q_-=u_-, \bar{u}_-,d_-,
\bar{d}_-,c_-, \bar{c}_-,s_-, \bar{s}_-)$ associated production up to the QCD
next-to-leading order (NLO) at the CERN Large Hadron Collider with subsequent
pure weak decay of $T$-odd mirror quark. We apply the PROSPINO scheme to avoid
the double counting problem and to keep the convergence of the perturbative QCD
description. The theoretical correlations between the integrated cross section
and the factorization and renormalization scale, the global symmetry-breaking
scale and the Yukawa coupling parameter are studied separately. We also provide
the kinematic distributions of the final decay products. Our numerical results
show that the NLO QCD correction reduces the scale uncertainty and enhances the
leading-order integrated cross section remarkably, with the $K$ factor varying
in the range of $1.41 \sim 1.68$ ($1.58 \sim 1.89$) as the increment of the
global symmetry-breaking scale $f$ from $500~{\rm GeV}$ to $1.5~{\rm TeV}$
($1.1~{\rm TeV}$) at the $\sqrt{s} = 14~{\rm TeV}$ ($8~{\rm TeV}$) LHC. We find
that it is possible to select the signal events of the $A_Hq_-$ production from
its background by putting proper cuts on the final leading jet and missing
energy.


title: Opacity of fluffy dust aggregates

abstract:
  Context. Dust grains coagulate to form dust aggregates in protoplanetary
disks. Their porosity can be extremely high in the disks. Although disk
emission may come from fluffy dust aggregates, the emission has been modeled
with compact grains. Aims. We aim to reveal the mass opacity of fluffy
aggregates from infrared to millimeter wavelengths with the filling factor
ranging from 1 down to $10^{-4}$. Methods. We use Mie calculations with an
effective medium theory. The monomers are assumed to be 0.1 ${\rm \mu m}$ sized
grains, which is much shorter than the wavelengths that we focus on. Results.
We find that the absorption mass opacity of fluffy aggregates are characterized
by the product $a\times f$, where $a$ is the dust radius and $f$ is the filling
factor, except for the interference structure. The scattering mass opacity is
also characterized by $af$ at short wavelengths while it is higher in more
fluffy aggregates at long wavelengths. We also derive the analytic formula of
the mass opacity and find that it reproduces the Mie calculations. We also
calculate the expected difference of the emission between compact and fluffy
aggregates in protoplanetary disks with a simple dust growth and drift model.
We find that compact grains and fluffy aggregates can be distinguished by the
radial distribution of the opacity index $\beta$. The previous observation of
the radial distribution of $\beta$ is consistent with the fluffy case, but more
observations are required to distinguish between fluffy or compact. In
addition, we find that the scattered light would be another way to distinguish
between compact grains and fluffy aggregates.


title: Towards the Framework of Information Security

abstract:
  Todays modern society is extremely dependent on computer based information
systems. Many of the organizations would simply not be able to function
properly without services provided by these systems, just like financing
organizations. Although interruption might decrease the efficiency of an
organization, theft or unintentional disclosure of entrusted private data could
have more serious consequences, such as legal actions as well as loss of
business due to lack of trust from potential users. This dependence on
information systems has lead to a need for securing these systems and this in
turn has created a need for knowing how secure they are. The introduction of
the information society has changed how people interact with government
agencies. Government agencies are now encouraged to uphold a 24-hour electronic
service to the citizens. The introduction of government services on the
Internet is meant to facilitate communication with agencies, decrease service
times and to lessen the amount of papers that needs to be processed. The
increased connectivity to the Internet results in a rising demand for
information security in these systems. In this article, we have discussed about
many file data breaches in the past and current history and they are going to
increase day by day as the reports by DataLossDB (Open Security Foundation)
organization, a non-profit organization in US.


title: Multi-Sensor Image Fusion Based on Moment Calculation

abstract:
  An image fusion method based on salient features is proposed in this paper.
In this work, we have concentrated on salient features of the image for fusion
in order to preserve all relevant information contained in the input images and
tried to enhance the contrast in fused image and also suppressed noise to a
maximum extent. In our system, first we have applied a mask on two input images
in order to conserve the high frequency information along with some low
frequency information and stifle noise to a maximum extent. Thereafter, for
identification of salience features from sources images, a local moment is
computed in the neighborhood of a coefficient. Finally, a decision map is
generated based on local moment in order to get the fused image. To verify our
proposed algorithm, we have tested it on 120 sensor image pairs collected from
Manchester University UK database. The experimental results show that the
proposed method can provide superior fused image in terms of several
quantitative fusion evaluation index.


title: Geometric Feature Based Face-Sketch Recognition

abstract:
  This paper presents a novel facial sketch image or face-sketch recognition
approach based on facial feature extraction. To recognize a face-sketch, we
have concentrated on a set of geometric face features like eyes, nose,
eyebrows, lips, etc and their length and width ratio because it is difficult to
match photos and sketches because they belong to two different modalities. In
this system, first the facial features/components from training images are
extracted, then ratios of length, width, and area etc. are calculated and those
are stored as feature vectors for individual images. After that the mean
feature vectors are computed and subtracted from each feature vector for
centering of the feature vectors. In the next phase, feature vector for the
incoming probe face-sketch is also computed in similar fashion. Here, K-NN
classifier is used to recognize probe face-sketch. It is experimentally
verified that the proposed method is robust against faces are in a frontal
pose, with normal lighting and neutral expression and have no occlusions. The
experiment has been conducted with 80 male and female face images from
different face databases. It has useful applications for both law enforcement
and digital entertainment.


title: What we can learn about quantum physics from a single qubit

abstract:
  We present an approach for teaching quantum physics at high school level
based on the simplest quantum system - the single quantum bit (qubit). We show
that many central concepts of quantum mechanics, including the superposition
principle, the stochastic behavior and state change under measurements as well
as the Heisenberg uncertainty principle can be understood using simple
mathematics, and can be illustrated using catchy visualizations. We discuss
abstract features of a qubit in general, and consider possible physical
realizations as well as various applications, e.g. in quantum cryptography.


title: General Rotational Surfaces in the Four-dimensional Minkowski Space

abstract:
  General rotational surfaces as a source of examples of surfaces in the
four-dimensional Euclidean space have been introduced by C. Moore. In this
paper we consider the analogue of these surfaces in the Minkowski 4-space. On
the base of our invariant theory of spacelike surfaces we study general
rotational surfaces with special invariants. We describe analytically the flat
general rotational surfaces and the general rotational surfaces with flat
normal connection. We classify completely the minimal general rotational
surfaces and the general rotational surfaces consisting of parabolic points.


title:
Structure, dynamics and light localization in self-induced plasma
  photonic lattices

abstract:
  Detailed two dimensional particle-in-cell (PIC) simulations and numerical
calculations of electron density profiles, based on a simplified model, were
performed to show for the first time that underdense plasma, induced by two
pairs of counterpropagating femtosecond-laser pulses in a gas, could be
manipulated by ponderomotive-optical lattices to form periodic structures.
These novel phenomena facilitate the localization and enhancement of the
generating laser pulse intensities by the self-induced plasma photonic lattices
(PPLs) and exhibit unique spatiotemporal dynamics. Variation of the initial
plasma density profile and the configuration of the interacting pulses enabled
control over the attainable PPL structures. It is predicted that by using a
non-uniform initial plasma density, light emission in a preferred direction
could be obtained.


title:
Ricci Dark Energy of Amended FRW Universe in Chern-Simon Modified
  Gravity

abstract:
  The energy density of the universe is proportional to the Ricci scalar
curvature in the dynamical Chern-Simon (CS) modified gravity. In this paper, we
consider the Amended Friedman-Robertson-Walker (AFRW) universe and explore its
scale factor and the Ricci Dark Energy. THese turned out to be well-defined and
definite. We compare the scale factors of FRW \cite{[17]}, Generalized
Chaplygin gas (GCG) \cite{[18]} and AFRW models graphically. The combined graph
of these models show that the behavior of both FRW and AFRW models is similar
as these overlap each other for choosing particular values of the integration
constants. Also, we draw a combined graph of the Ricci dark energy densities of
FRW and AFRW models, in CS gravity, and the energy density of GCG. It shows
that the densities of former two models are increasing with time while the
energy density of GCG is decreasing.


title:
Correlation functions of conserved currents in four dimensional
  conformal field theory with higher spin symmetry

abstract:
  We report some recent progress in the computation of the n-point correlation
functions of conserved currents in a class of four dimensional conformal field
theories with higher spin symmetry. Global conformal invariance leads to very
strong constraints on both the general form and the singularity structure of
the correlation functions of conserved currents. Namely, all these functions
have to be rational functions with at most double pole singularities. We show
that this implies that the 4-, 5- and 6-point correlation functions of the
(symmetric, conserved and traceless) stress-energy tensor are linear
combinations of the three free field expressions. Hence, in four dimensions,
any globally conformal invariant theory is free.


title:
Radiation of a neutral polarizable particle moving uniformly through a
  thermal radiation field

abstract:
  We discuss the properties of thermal electromagnetic radiation produced by a
neutral polarizable nanoparticle moving with an arbitrary relativistic velocity
in a heated vacuum background with a fixed temperature. We show that the
particle in its own rest frame acquires the radiation temperature of vacuum,
multiplied by a velocity-dependent factor, and then emits thermal photons
predominantly in the forward direction. The intensity of radiation proves to be
much higher than for the particle at rest. For metal particles with high
energy, the ratio of emitted and absorbed radiation power is proportional to
the Lorentz-factor squared.


title:
The Local Hamiltonian problem on a line with eight states is
  QMA-complete

abstract:
  The Local Hamiltonian problem is the problem of estimating the least
eigenvalue of a local Hamiltonian, and is complete for the class QMA. The 1D
problem on a chain of qubits has heuristics which work well, while the 13-state
qudit case has been shown to be QMA-complete. We show that this problem remains
QMA-complete when the dimensionality of the qudits is brought down to 8.


title:
Radiative decays of radially excited pseudoscalar mesons in the extended
  Nambu--Jona-Lasinio model

abstract:
  In the extended NJL model the radiative decay widths of the radially excited
states of the pseudoscalar $\pi$, $\eta$, and $\eta'$ mesons are calculated.
The predictions for the decay widths of the processes
$\pi(1300)\longrightarrow(\rho^0,\omega)\gamma$,
$\eta(1295)\longrightarrow(\rho^0,\omega,\phi)\gamma$, and
$\eta(1475)\longrightarrow(\rho^0,\omega,\phi)\gamma$ are given. Nowadays,
there are no solid experimental data for these processes. The comparison of the
results obtained in the framework of the standard and the extended NJL models
for decays of the ground states of mesons is given. It is shown that these
calculations correspond to each other and are also in satisfactory agreement
with experimental data. This allows one to expect that the extended NJL can
give reliable predictions for the excited states of mesons.


title: Electron-electron interactions in bilayer graphene quantum dots

abstract:
  A parabolic quantum dot (QD) as realized by biasing nanostructured gates on
bilayer graphene is investigated in the presence of electron-electron
interaction. The energy spectrum and the phase diagram reveal unexpected
transitions as function of a magnetic field. For example, in contrast to
semiconductor QDs, we find a novel valley transition rather than only the usual
singlet-triplet transition in the ground state of the interacting system. The
origin of these new features can be traced to the valley degree of freedom in
bilayer graphene. These transitions have important consequences for cyclotron
resonance experiments.


title: A stochastic HJB equation for optimal control of forward-backward SDEs

abstract:
  We study optimal stochastic control problems of general coupled systems of
forward-backward stochastic differential equations with jumps. By means of the
It\^o-Ventzell formula the system is transformed to a controlled backward
stochastic partial differential equation (BSPDE) with jumps. Using a comparison
principle for such BSPDEs we obtain a general stochastic Hamilton-Jacobi-
Bellman (HJB) equation for such control problems. In the classical Markovian
case with optimal control of jump diffusions, the equation reduces to the
classical HJB equation.
  The results are applied to study risk minimization in financial markets.


title:
Oracle Properties and Finite Sample Inference of the Adaptive Lasso for
  Time Series Regression Models

abstract:
  We derive new theoretical results on the properties of the adaptive least
absolute shrinkage and selection operator (adaptive lasso) for time series
regression models. In particular, we investigate the question of how to conduct
finite sample inference on the parameters given an adaptive lasso model for
some fixed value of the shrinkage parameter. Central in this study is the test
of the hypothesis that a given adaptive lasso parameter equals zero, which
therefore tests for a false positive. To this end we construct a simple testing
procedure and show, theoretically and empirically through extensive Monte Carlo
simulations, that the adaptive lasso combines efficient parameter estimation,
variable selection, and valid finite sample inference in one step. Moreover, we
analytically derive a bias correction factor that is able to significantly
improve the empirical coverage of the test on the active variables. Finally, we
apply the introduced testing procedure to investigate the relation between the
short rate dynamics and the economy, thereby providing a statistical foundation
(from a model choice perspective) to the classic Taylor rule monetary policy
model.


title:
`Hits' emerge through self-organized coordination in collective response
  of free agents

abstract:
  Individuals in free societies frequently exhibit striking coordination when
making independent decisions en masse. Examples include the regular appearance
of hit products or memes with substantially higher popularity compared to their
otherwise equivalent competitors, or extreme polarization in public opinion.
Such segregation of events manifests as bimodality in the distribution of
collective choices. Here we quantify how apparently independent choices made by
individuals result in a significantly polarized but stable distribution of
success in the context of the box-office performance of movies and show that it
is an emergent feature of a system of non-interacting agents who respond to
sequentially arriving signals. The aggregate response exhibits extreme
variability amplifying much smaller differences in individual cost of adoption.
Due to self-organization of the competitive landscape, most events elicit only
a muted response but a few stimulate widespread adoption, emerging as "hits".


title:
The Study on the Effects of Chromaticity and Magnetic Field Tracking
  Errors at CSNS/RCS

abstract:
  The Rapid Cycling Synchrotron (RCS) is a key component of the China
Spallation Neutron Source (CSNS). For this type of high intensity proton
synchrotron, the chromaticity, space charge effects and magnetic field tracking
errors between the quadrupoles and the dipoles can induce beta function
distortion and tune shift, and induce resonances. In this paper the combined
effects of chromaticity, magnetic field tracking errors and space charge on
beam dynamics at CSNS/RCS are studied systemically. 3-D simulations with
different magnetic field tracking errors are performed by using the code ORBIT,
and the simulation results are compared with the case without tracking errors.


title:
Scalable iterative methods for sampling from massive Gaussian random
  vectors

abstract:
  Sampling from Gaussian Markov random fields (GMRFs), that is multivariate
Gaussian ran- dom vectors that are parameterised by the inverse of their
covariance matrix, is a fundamental problem in computational statistics. In
this paper, we show how we can exploit arbitrarily accu- rate approximations to
a GMRF to speed up Krylov subspace sampling methods. We also show that these
methods can be used when computing the normalising constant of a large
multivariate Gaussian distribution, which is needed for both any
likelihood-based inference method. The method we derive is also applicable to
other structured Gaussian random vectors and, in particu- lar, we show that
when the precision matrix is a perturbation of a (block) circulant matrix, it
is still possible to derive O(n log n) sampling schemes.


title:
High-precision measurement of atmospheric mass-squared splitting with
  T2K and NOvA

abstract:
  A precise measurement of the atmospheric mass-squared splitting |\Delta
m^2_{\mu\mu}| is crucial to establish the three-flavor paradigm and to
constrain the neutrino mass models. In addition, a precise value of |\Delta
m^2_{\mu\mu}| will significantly enhance the hierarchy reach of future
medium-baseline reactor experiments like JUNO and RENO-50. In this work, we
explore the precision in |\Delta m^2_{\mu\mu}| that will be available after the
full runs of T2K and NOvA. We find that the combined data will be able to
improve the precision in |\Delta m^2_{\mu\mu}| to sub-percent level for maximal
2-3 mixing. Depending on the true value of \sin^2\theta_{23} in the
currently-allowed 3 sigma range, the precision in |\Delta m^2_{\mu\mu}| will
vary from 0.87% to 1.24%. We further demonstrate that this is a robust
measurement as it remains almost unaffected by the present uncertainties in
\theta_{13}, \delta_{CP}, the choice of mass hierarchy, and the systematic
errors.


title: Universal fluctuations in the growth of semiconductor thin films

abstract:
  Scaling of surface fluctuations of polycrystalline CdTe/Si(100) films grown
by hot wall epitaxy are studied. The growth exponent of surface roughness and
the dynamic exponent of the auto-correlation function in the mound growth
regime agree with the values of the Kardar-Parisi-Zhang (KPZ) class. The scaled
distributions of heights, local roughness, and extremal heights show remarkable
collapse with those of the KPZ class, giving the first experimental observation
of KPZ distributions in $2+1$ dimensions. Deviations from KPZ values in the
long-time estimates of dynamic and roughness exponents are explained by
spurious effects of multi-peaked coalescing mounds and by effects of grain
shapes. Thus, this scheme for investigating universality classes of growing
films advances over the simple comparison of scaling exponents.


title:
The Factorization method for three dimensional Electrical Impedance
  Tomography

abstract:
  The use of the Factorization method for Electrical Impedance Tomography has
been proved to be very promising for applications in the case where one wants
to find inhomogeneous inclusions in a known background. In many situations, the
inspected domain is three dimensional and is made of various materials. In this
case, the main challenge in applying the Factorization method consists in
computing the Neumann Green's function of the background medium. We explain how
we solve this difficulty and demonstrate the capability of the Factorization
method to locate inclusions in realistic inhomogeneous three dimensional
background media from simulated data obtained by solving the so-called complete
electrode model. We also perform a numerical study of the stability of the
Factorization method with respect to various modelling errors.


title: Symmetry-forced rigidity of frameworks on surfaces

abstract:
  A fundamental theorem of Laman characterises when a bar-joint framework
realised generically in the Euclidean plane admits a non-trivial continuous
deformation of its vertices. This has recently been extended in two ways.
Firstly to frameworks that are symmetric with respect to some point group but
are otherwise generic, and secondly to frameworks in Euclidean 3-space that are
constrained to lie on 2-dimensional algebraic varieties.
  We combine these two settings and consider the rigidity of symmetric
frameworks realised on such surfaces. By extending the orbit matrix techniques
of [32, 12], we prove necessary conditions for a framework to be
symmetry-forced rigid (i.e., to have no non-trivial symmetry-preserving motion)
for any group and any surface. In the cases when the surface is a sphere, a
cylinder or a cone we use Henneberg-type inductive constructions on
group-labeled quotient graphs to prove that these conditions are also
sufficient for a number of symmetry groups, including rotation, reflection,
inversion and dihedral symmetry. For the remaining groups - as well as for
other types of surfaces - we provide some observations and conjectures.


title:
Asymptotic analysis of the transmission eigenvalue problem for a
  Dirichlet obstacle coated by a thin layer of non-absorbing media

abstract:
  We consider the transmission eigenvalue problem for an impenetrable obstacle
with Dirichlet boundary condition surrounded by a thin layer of non-absorbing
inhomogeneous material. We derive a rigorous asymptotic expansion for the first
transmission eigenvalue with respect to the thickness of the thin layer. Our
convergence analysis is based on a Max-Min principle and an iterative approach
which involves estimates on the corresponding eigenfunctions. We provide
explicit expressions for the terms in the asymptotic expansion up to order
three.


title:
Low Complexity Decoding for Punctured Trellis-Coded Modulation Over
  Intersymbol Interference Channels

abstract:
  Classical trellis-coded modulation (TCM) as introduced by Ungerboeck in
1976/1983 uses a signal constellation of twice the cardinality compared to an
uncoded transmission with one bit of redundancy per PAM symbol, i.e.,
application of codes with rates $\frac{n-1}{n}$ when $2^{n}$ denotes the
cardinality of the signal constellation. The original approach therefore only
comprises integer transmission rates, i.e., $R=\left\{ 2,\,3,\,4\,\ldots
\right\}$, additionally, when transmitting over an intersymbol interference
(ISI) channel an optimum decoding scheme would perform equalization and
decoding of the channel code jointly. In this paper, we allow rate adjustment
for TCM by means of puncturing the convolutional code (CC) on which a TCM
scheme is based on. In this case a nontrivial mapping of the output symbols of
the CC to signal points results in a time-variant trellis. We propose an
efficient technique to integrate an ISI-channel into this trellis and show that
the computational complexity can be significantly reduced by means of a reduced
state sequence estimation (RSSE) algorithm for time-variant trellises.


title:
Equilibrium measures for a class of potentials with discrete rotational
  symmetries

abstract:
  In this note the logarithmic energy problem with external potential
$|z|^{2n}+tz^d+\bar{t}\bar{z}^d$ is considered in the complex plane, where $n$
and $d$ are positive integers satisfying $d\leq 2n$. Exploiting the discrete
rotational invariance of the potential, a simple symmetry reduction procedure
is used to calculate the equilibrium measure for all admissible values of $n,d$
and $t$.
  It is shown that, for fixed $n$ and $d$, there is a critical value
$|t|=t_{cr}$ such that the support of the equilibrium measure is simply
connected for $|t|<t_{cr}$ and has $d$ connected components for $|t|>t_{cr}$.


title:
Enhanced Visible Light Photocatalytic Activity for TiO2 Nanotube Array
  Films by Codoping with Tungsten and Nitrogen

abstract:
  A series of W, N codoped TiO2 nanotube arrays with different dopant contents
were fabricated by anodizing in association with hydrothermal treatment. The
samples were characterized by scanning electron microscopy, X-ray diffraction,
X-ray photoelectron spectroscopy, and ultraviolet-visible light diffuse
reflection spectroscopy. Moreover, the photocatalytic activity of W and N
codoped TiO2 nanotube arrays was evaluated by degradation of methylene blue
under visible light irradiation.


title: Subgroups of finite Abelian groups having rank two via Goursat's lemma

abstract:
  Using Goursat's lemma for groups, a simple representation and the invariant
factor decompositions of the subgroups of the group Z_m x Z_n are deduced,
where m and n are arbitrary positive integers. As consequences, explicit
formulas for the total number of subgroups, the number of subgroups with a
given invariant factor decomposition, and the number of subgroups of a given
order are obtained.


title: Electronic antiferromagnetic correlations in cuprates phase diagram

abstract:
  Modern state-of-the-art techniques allow us to explore the magnetic and
electronic structures of cuprates throughout the whole phase diagram, which
defines the central questions on their emergent high temperature
superconductivity. However, a simplified and unified description of the order
parameters in these colorful phases together with their complex relations is
still undetermined. Here we establish this phase diagram and the related
structures based on recent experimental progresses with emphasizing several
essential equations, and we try to understand them under the framework of
antiferromagnetic (AF) correlation using the simplest mathematics. This model
independent description of cuprates phase diagram gives both clues and
constraints to a final microscopic theory of the cuprates superconductivity.