title: Routing and Sorting Via Matchings On Graphs

abstract:
  The paper is divided in to two parts. In the first part we present some new
results for the \textit{routing via matching} model introduced by Alon et
al\cite{5}. This model can be viewed as a communication scheme on a distributed
network. The nodes in the network can communicate via matchings (a step), where
a node exchanges data with its partner. Formally, given a connected graph $G$
with vertices labeled from $[1,...,n]$ and a permutation $\pi$ giving the
destination of pebbles on the vertices the problem is to find a minimum step
routing scheme. This is denoted as the routing time $rt(G,\pi)$ of $G$ given
$\pi$. In this paper we present the following new results, which answer one of
the open problems posed in \cite{5}: 1) Determining whether $rt(G,\pi)$ is $\le
2$ can be done in $O(n^{2.5})$ deterministic time for any arbitrary connected
graph $G$. 2) Determining whether $rt(G,\pi)$ is $\le k$ for any $k \ge 3$ is
NP-Complete. In the second part we study a related property of graphs, which
measures how easy it is to design sorting networks using only the edges of a
given graph. Informally, \textit{sorting number} of a graph is the minimum
depth sorting network that only uses edges of the graph. Many of the classical
results on sorting networks can be represented in this framework. We show that
a tree with maximum degree $\Delta$ can accommodate a $O(\min(n\Delta^2,n^2))$
depth sorting network. Additionally, we give two instance of trees for which
this bound is tight.


title:
Fermionic Dark Matter through a Light Pseudoscalar Portal: Hints from
  the DAMA Results

abstract:
  We study the fermionic dark matter (DM) particle interacting with Standard
Model quarks via a light pseudoscalar mediator. We consider separately the
scenarios for which the DM-pseudoscalar coupling is $CP$ conserving or $CP$
violating. We show that taking a contact interaction is not suitable, even when
the mediator has a mass of the same order of magnitude as the typical momentum
transfer at the direct-detection experiments, such that the allowed DAMA region
is excluded or considerably modified by the correct relic density requirement.
The DAMA result seems to indicate that the $CP$-violating interaction is
dominant at direct searches. We find that, if the proton-to-neutron effective
coupling ratio is $-60\sim -40$, the exclusion limits set by SuperCDMS,
XENON100, and LUX are highly suppressed, and the DAMA signal can thus be easily
reconciled with these null measurements. For this model, the allowed region
determined by the DAMA signal and correct relic density can successfully
satisfy the conditions required by the thermal equilibrium, big bang
nucleosynthesis, and DM self-interactions. The results of future measurements
on flavor physics will provide important constraints on the related models.
Precise measurements performed by COUPP, PICASSO, SIMPLE and KIMS should be
able to test this model in the near future.


title:
Potentially Predictive Variance Reducing Subsample Locations in Local
  Gaussian Process Regression

abstract:
  Gaussian process models are commonly used as emulators for computer
experiments. However, developing a Gaussian process emulator can be
computationally prohibitive when the number of experimental samples is even
moderately large. Local Gaussian process approximation (Gramacy and Apley,
2015) was proposed as an accurate and computationally feasible emulation
alternative. However, constructing local sub-designs specific to predictions at
a particular location of interest remains a substantial computational
bottleneck to the technique. In this paper, two computationally efficient
neighborhood search limiting techniques are proposed, a maximum distance method
and a feature approximation method. Two examples demonstrate that the proposed
methods indeed save substantial computation while retaining emulation accuracy.


title: A note on successive coefficients of convex functions

abstract:
  In this note, we investigate the supremum and the infimum of the functional
$|a_{n+1}|-|a_{n}|$ for functions, convex and analytic on the unit disk, of the
form $f(z)=z+a_2z^2+a_3z^3+\dots.$ We also consider the related problem to
maximize the functional $|a_{n+1}-a_{n}|$ for convex functions $f$ with
$f"(0)=p$ for a prescribed $p\in[0,2].$


title:
Slipping magnetic reconnections with multiple flare ribbons during an
  X-class solar flare

abstract:
  With the observations of the Solar Dynamics Observatory, we present the
slipping magnetic reconnections with multiple flare ribbons (FRs) during an
X1.2 eruptive flare on 2014 January 7. A center negative polarity was
surrounded by several positive ones, and there appeared three FRs. The three
FRs showed apparent slipping motions, and hook structures formed at their ends.
Due to the moving footpoints of the erupting structures, one tight
semi-circular hook disappeared after the slippage along its inner and outer
edge, and coronal dimmings formed within the hook. The east hook also faded as
a result of the magnetic reconnection between the arcades of a remote filament
and a hot loop that was impulsively heated by the under flare loops. Our
results are accordant with the slipping magnetic reconnection regime in 3D
standard model for eruptive flares. We suggest that complex structures of the
flare is likely a consequence of the more complex flux distribution in the
photosphere, and the eruption involves at least two magnetic reconnections.


title: Compositional security and collateral leakage

abstract:
  In quantitative information flow we say that program $Q$ is "at least as
secure as" $P$ just when the amount of secret information flowing from $Q$ is
never more than flows from $P$, with of course a suitable quantification of
"flow". This secure-refinement order $\sqsubseteq$ is compositional just when
$P{\sqsubseteq}Q$ implies ${\cal C}(P){\sqsubseteq}{\cal C}(Q)$ for any context
${\cal C}$, again with a suitable definition of "context".
  Remarkable however is that leaks caused by executing $P,Q$ might not be
limited to their declared variables: they might impact correlated secrets in
variables declared and initialised in some broader context to which $P,Q$ do
not refer even implicitly. We call such leaks collateral because their effect
is felt in domains of which (the programmers of) $P, Q$ might be wholly
unaware: our inspiration is the "Dalenius" phenomenon for statistical
databases.
  We show that a proper treatment of these collateral leaks is necessary for a
compositional program semantics for read/write "open" programs. By adapting a
recent Hidden-Markov denotational model for non-interference security, so that
it becomes "collateral aware", we give techniques and examples (e.g.\
public-key encryption) to show how collateral leakage can be calculated and
then bounded in its severity.


title: Prediction-error of Prediction Error (PPE)-based Reversible Data Hiding

abstract:
  This paper presents a novel reversible data hiding (RDH) algorithm for
gray-scaled images, in which the prediction-error of prediction error (PPE) of
a pixel is used to carry the secret data. In the proposed method, the pixels to
be embedded are firstly predicted with their neighboring pixels to obtain the
corresponding prediction errors (PEs). Then, by exploiting the PEs of the
neighboring pixels, the prediction of the PEs of the pixels can be determined.
And, a sorting technique based on the local complexity of a pixel is used to
collect the PPEs to generate an ordered PPE sequence so that, smaller PPEs will
be processed first for data embedding. By reversibly shifting the PPE histogram
(PPEH) with optimized parameters, the pixels corresponding to the altered PPEH
bins can be finally modified to carry the secret data. Experimental results
have implied that the proposed method can benefit from the prediction procedure
of the PEs, sorting technique as well as parameters selection, and therefore
outperform some state-of-the-art works in terms of payload-distortion
performance when applied to different images.


title: On Classical and Quantum Logical Entropy: The analysis of measurement

abstract:
  The notion of a partition on a set is mathematically dual to the notion of a
subset of a set, so there is a logic of partitions dual to Boole's logic of
subsets (Boolean subset logic is usually mis-specified as the special case of
"propositional" logic). The notion of an element of a subset has as its dual
the notion of a distinction of a partition (a pair of elements in different
blocks). Boole developed finite logical probability as the normalized counting
measure on elements of subsets so there is a dual concept of logical entropy
which is the normalized counting measure on distinctions of partitions. Thus
the logical notion of information is a measure of distinctions. Classical
logical entropy also extends naturally to the notion of quantum logical entropy
which provides a more natural and informative alternative to the usual Von
Neumann entropy in quantum information theory. The quantum logical entropy of a
post-measurement density matrix has the simple interpretation as the
probability that two independent measurements of the same state using the same
observable will have different results. The main result of the paper is that
this increase in quantum logical entropy due to a projective measurement of a
pure state is the sum of the absolute squares of the off-diagonal entries
(`coherences') of the pure state density matrix that are zeroed (decohered) by
the measurement, i.e., the measure of the distinctions (`decoherences') created
by the measurement. The Von Neumann entropy provides no such analysis of
measurement. That result is also classically modelled using ordinary partitions
and density matrices for such partitions in the pedagogical model of QM/Sets
with point probabilities--which for a fixed basis is just sampling a real r.v.
in classical finite probability theory.


title:
Segmentation-free x-ray energy spectrum estimation for computed
  tomography

abstract:
  X-ray energy spectrum plays an essential role in imaging and related tasks.
Due to the high photon flux of clinical CT scanners, most of the spectrum
estimation methods are indirect and are usually suffered from various
limitations. The recently proposed indirect transmission measurement-based
method requires at least the segmentation of one material, which is
insufficient for CT images of highly noisy and with artifacts. To combat for
the bottleneck of spectrum estimation using segmented CT images, in this study,
we develop a segmentation-free indirect transmission measurement based energy
spectrum estimation method using dual-energy material decomposition. The
general principle of the method is to compare polychromatic forward projection
with raw projection to calibrate a set of unknown weights which are used to
express the unknown spectrum together with a set of model spectra. After
applying dual-energy material decomposition using high- and low-energy raw
projection data, polychromatic forward projection is conducted on
material-specific images. The unknown weights are then iteratively updated to
minimize the difference between the raw projection and estimated projection.
Both numerical simulations and experimental head phantom are used to evaluate
the proposed method. The results indicate that the method provides accurate
estimate of the spectrum and it may be attractive for dose calculations,
artifacts correction and other clinical applications.


title: Information retrieval from black holes

abstract:
  It is generally believed that, when matter collapses to form a black hole,
the complete information about the initial state of the matter cannot be
retrieved by future asymptotic observers, through local measurements. This is
contrary to the expectation from a unitary evolution in quantum theory and
leads to (a version of) the black hole information paradox. Classically,
nothing else, apart from mass, charge and angular momentum is expected to be
revealed to such asymptotic observers after the formation of a black hole.
Semi-classically, black holes evaporate after their formation through the
Hawking radiation. The dominant part of the radiation is expected to be thermal
and hence one cannot know anything about the initial data from the resultant
radiation. However, there can be sources of distortions which make the
radiation non-thermal. Although the distortions are not strong enough to make
the evolution unitary, these distortions carry some part of information
regarding the in-state. In this work, we show how one can decipher the
information about the in-state of the field from these distortions. We show
that the distortions of a particular kind --- which we call {\it non-vacuum
distortions} --- can be used to \emph{fully} reconstruct the initial data. The
asymptotic observer can do this operationally by measuring certain well-defined
observables of the quantum field at late times. We demonstrate that a general
class of in-states encode all their information content in the correlation of
late time out-going modes. Further, using a $1+1$ dimensional CGHS model to
accommodate back-reaction self-consistently, we show that observers can also
infer and track the information content about the initial data, during the
course of evaporation, unambiguously. Implications of such information
extraction are discussed.


title:
Extraction of Active Regions and Coronal Holes from EUV Images Using the
  Unsupervised Segmentation Method in the Bayesian Framework

abstract:
  The solar corona is the origin of very dynamic events that are mostly
produced in active regions (AR) and coronal holes (CH). The exact location of
these large-scale features can be determined by applying image-processing
approaches to extreme-ultraviolet (EUV) data.
  We here investigate the problem of segmentation of solar EUV images into ARs,
CHs, and quiet-Sun (QS) images in a firm Bayesian way. On the basis of Bayes'
rule, we need to obtain both prior and likelihood models. To find the prior
model of an image, we used a Potts model in non-local mode. To construct the
likelihood model, we combined a mixture of a Markov-Gauss model and non-local
means. After estimating labels and hyperparameters with the Gibbs estimator,
cellular learning automata were employed to determine the label of each pixel.
  We applied the proposed method to a Solar Dynamics Observatory/ Atmospheric
Imaging Assembly (SDO/AIA) dataset recorded during 2011 and found that the mean
value of the filling factor of ARs is 0.032 and 0.057 for CHs. The power-law
exponents of the size distribution of ARs and CHs were obtained to be -1.597
and -1.508, respectively, with the maximum likelihood estimator method. When we
compare the filling factors of our method with a manual selection approach and
the SPoCA algorithm, they are highly compatible.


title:
The Conway-Miyamoto correspondences for the Fischer 3-transposition
  groups

abstract:
  In this paper, we present a general construction of 3-transposition groups as
automorphism groups of vertex operator algebras. Applying to the moonshine
vertex operator algebra, we establish the Conway-Miyamoto correspondences
between Fischer 3-transposition groups $\mathrm{Fi}_{23}$ and
$\mathrm{Fi}_{22}$ and $c=25/28$ and $c=11/12$ Virasoro vectors of subalgebras
of the moonshine vertex operator algebra.


title:
Emergent geometry from field theory: Wilson's renormalization group
  revisited

abstract:
  We find a geometrical description from a field theoretical setup based on
Wilson's renormalization group in real space. We show that renormalization
group equations of coupling parameters encode the metric structure of an
emergent curved space, regarded to be an Einstein equation for the emergent
gravity. Self-consistent equations of local order-parameter fields with an
emergent metric turn out to describe low energy dynamics of a strongly coupled
field theory, analogous to the Maxwell equation of the Einstein-Maxwell theory
in the AdS$_{d+2}$/CFT$_{d+1}$ duality conjecture. We claim that the
AdS$_{3}$/CFT$_{2}$ duality may be interpreted as Landau-Ginzburg theory
combined with Wilson's renormalization group, which introduces vertex
corrections into the Landau-Ginzburg theory in the large$-N_{s}$ limit, where
$N_{s}$ is the number of fermion flavors.


title:
Crossed responses of spin and orbital magnetism in topological
  insulators

abstract:
  Crossed magnetic responses between spin and orbital angular momentum are
studied in time-reversal symmetric topological insulators. Due to spin-orbit
coupling in the quantum spin Hall systems and three-dimensional topological
insulators, the magnetic susceptibility has crossed (intersectional) components
between spin and orbital part of magnetism. In this study, the crossed
susceptibility for the orbital magnetization is studied in two- and
three-dimensional topological insulator models, in which an external magnetic
field interacts with the electron spin by Zeeman coupling via distinct
g-factors for conduction and valence energy bands. The crossed susceptibility
in two-dimensional quantum spin Hall insulators shows a quantized signature of
the $\mathbb{Z}_2$ topological phase in response to Zeeman coupling via an
averaged g-factor, and the quantization persists even when
$\sigma^z$-conservation of electrons is broken by a tilted magnetic field. The
bulk orbital magnetization is interpreted by the persistent edge current
attributed to the chiral anomaly at the (1+1)-dimensional boundary. In
three-dimensional topological insulators, we found that the crossed
susceptibility is proportional to the difference of g-factors of conduction and
valence electrons, which is qualitatively different from the two-dimensional
case. Steep changes of the crossed susceptibility in three dimensions at the
phase transition points are explained by the surface Dirac fermion theory.
Finally, dependence of the crossed susceptibility on g-factors in two- and
three-dimensional cases is discussed from the viewpoint of time-reversal and
particle-hole symmetries.


title: Time-Frequency analysis via the Fourier Representation

abstract:
  The nonstationary nature of signals and nonlinear systems require the
time-frequency representation. In time-domain signal, frequency information is
derived from the phase of the Gabor's analytic signal which is practically
obtained by the inverse Fourier transform. This study presents time-frequency
analysis by the Fourier transform which maps the time-domain signal into the
frequency-domain. In this study, we derive the time information from the phase
of the frequency-domain signal and obtain the time-frequency representation. In
order to obtain the time information in Fourier domain, we define the concept
of `frequentaneous time' which is frequency derivative of phase. This is very
similar to the group delay, which is also defined as frequency derivative of
phase and it provide physical meaning only when it is positive. The
frequentaneous time is always positive or negative depending upon whether
signal is defined for only positive or negative times, respectively. If a
signal is defined for both positive and negative times, then we divide the
signal into two parts, signal for positive times and signal for negative times.
The proposed frequentaneous time and Fourier transform based time-frequency
distribution contains only those frequencies which are present in the Fourier
spectrum. Simulations and numerical results, on many simulated as well as read
data, demonstrate the efficacy of the proposed method for the time-frequency
analysis of a signal.


title:
Numerical study of the giant nonlocal resistance in spin-orbital coupled
  graphene

abstract:
  Recent experiments find the signal of giant nonlocal resistance $R_{NL}$ in
H-shaped graphene samples due to the spin/valley Hall effect. Interestingly,
when the Fermi energy deviates from the Dirac point, $R_{NL}$ decreases to zero
much more rapidly compared with the local resistance $R_L$, and the well-known
relation of $R_{NL}\propto R_L^3$ is not satisfied. In this work, based on the
non-equilibrium Green's function method, we explain such transport phenomena in
the H-shaped graphene with Rashba spin-orbit coupling. When the Fermi energy is
near the Dirac point, the nonlocal resistance is considerably large and is much
sharper than the local one. Moreover, the relationship between the Rashba
effect and the fast decay of $R_{NL}$ compared with $R_L$ is further
investigated. We find that the Rashba effect does not contribute not only to
the fast decay but also to the peak of $R_{NL}$ itself. Actually, it is the
extremely small density of states near the Dirac point that leads to the large
peak of $R_{NL}$, while the fast decay results from the quasi-ballistic
mechanism. Finally, we revise the classic formula $R_{NL}\propto R_L^3$ by
replacing $R_{NL}$ with $R_{Hall}$, which represents the nonlocal resistance
merely caused by the spin Hall effect, and the relation holds well.


title:
Selective Convolutional Descriptor Aggregation for Fine-Grained Image
  Retrieval

abstract:
  Deep convolutional neural network models pre-trained for the ImageNet
classification task have been successfully adopted to tasks in other domains,
such as texture description and object proposal generation, but these tasks
require annotations for images in the new domain. In this paper, we focus on a
novel and challenging task in the pure unsupervised setting: fine-grained image
retrieval. Even with image labels, fine-grained images are difficult to
classify, let alone the unsupervised retrieval task. We propose the Selective
Convolutional Descriptor Aggregation (SCDA) method. SCDA firstly localizes the
main object in fine-grained images, a step that discards the noisy background
and keeps useful deep descriptors. The selected descriptors are then aggregated
and dimensionality reduced into a short feature vector using the best practices
we found. SCDA is unsupervised, using no image label or bounding box
annotation. Experiments on six fine-grained datasets confirm the effectiveness
of SCDA for fine-grained image retrieval. Besides, visualization of the SCDA
features shows that they correspond to visual attributes (even subtle ones),
which might explain SCDA's high mean average precision in fine-grained
retrieval. Moreover, on general image retrieval datasets, SCDA achieves
comparable retrieval results with state-of-the-art general image retrieval
approaches.


title:
Two-qubit universal and state-dependent quantum cloning machine and
  quantum correlation broadcasting

abstract:
  Due to the axioms of quantum mechanics, perfect cloning of an unknown quantum
state is impossible. But since imperfect cloning is still possible, a question
arises: "Is there an optimal quantum cloning machine?" Buzek and Hillery answer
to this question and construct their famous B-H quantum cloning machine. The
B-H machine clones state of an arbitrary single qubit in optimal manner and
hence it is universal. Generalizing this machine for two-qubit system is
straightforward, but this procedure does not preserve quantum correlation
existing in bipartite state in optimal manner and also, during this procedure,
this machine loses its universality and becomes a state-dependent cloning
machine. In this paper we propose an optimal universal local quantum state
cloner for two qubit systems. Also we present two classes of state-dependent
local quantum copying machine. Furthermore, we investigate local broadcasting
of two aspects of quantum correlations, i.e., quantum entanglement and quantum
discord defined, respectively, within the entanglement-separability paradigm
and from an information-theoretic perspective. The results show that although
quantum correlation is in general very fragile during broadcasting procedure,
quantum discord is broadcasted more robustly than quantum entanglement.


title:
Persistent superfluid flow arising from the He-McKellar-Wilkens effect
  in molecular dipolar condensates

abstract:
  We show that the He-McKellar-Wilkens effect can induce a persistent flow in a
Bose-Einstein condensate of polar molecules confined in a toroidal trap, with
the dipolar interaction mediated via an electric dipole moment. For
Bose-Einstein condensates of atoms with a magnetic dipole moment, we show that
although it is theoretically possible to induce persistent flow via the
Aharonov-Casher effect, the strength of electric field required is prohibitive.
We also outline an experimental geometry tailored specifically for observing
the He-McKellar-Wilkens effect in toroidally-trapped condensates.


title: A Unified, Hardware-Fitted, Cross-GPU Performance Model

abstract:
  We present a mechanism to symbolically gather performance-relevant operation
counts from numerically-oriented subprograms (`kernels') expressed in the Loopy
programming system, and apply these counts in a simple, linear model of kernel
run time. We use a series of `performance-instructive' kernels to fit the
parameters of a unified model to the performance characteristics of GPU
hardware from multiple hardware generations and vendors. We evaluate the
predictive power of the model on a broad array of computational kernels
relevant to scientific computing. In terms of the geometric mean, our simple,
vendor- and GPU-type-independent model achieves relative accuracy comparable to
that of previously published work using hardware specific models.


title: On thermalization of two-level quantum systems

abstract:
  Providing the microscopic behavior of a thermalization process has always
been an intriguing issue. There are several models of thermalization, which
often requires interaction of the system under consideration with the
microscopic constituents of the macroscopic heat bath. With an aim to simulate
such a thermalization process, here we look at the thermalization of a
two-level quantum system under the action of a Markovian master equation
corresponding to memory-less action of a heat bath, kept at a certain
temperature, using a single-qubit ancilla. A two-qubit interaction Hamiltonian
($H_{th}$, say) is then designed -- with a single-qubit thermal state as the
initial state of the ancilla -- which gives rise to thermalization of the
system qubit in the infinite time limit. Further, we study the general form of
Hamiltonian, of which ours is a special case, and look for the conditions for
thermalization to occur. We also derive a Lindblad-like non-Markovian master
equation for the system dynamics under the general form of system-ancilla
Hamiltonian.


title:
A Band-independent Variable Step Size Proportionate Normalized Subband
  Adaptive Filter Algorithm

abstract:
  Proportionate-type normalized suband adaptive filter (PNSAF-type) algorithms
are very attractive choices for echo cancellation. To further obtain both fast
convergence rate and low steady-state error, in this paper, a variable step
size (VSS) version of the presented improved PNSAF (IPNSAF) algorithm is
proposed by minimizing the square of the noise-free a posterior subband error
signals. A noniterative shrinkage method is used to recover the noise-free a
priori subband error signals from the noisy subband error signals.
Significantly, the proposed VSS strategy can be applied to any other PNSAF-type
algorithm, since it is independent of the proportionate principles. Simulation
results in the context of acoustic echo cancellation have demonstrated the
effectiveness of the proposed method.


title:
LSTM-CF: Unifying Context Modeling and Fusion with LSTMs for RGB-D Scene
  Labeling

abstract:
  Semantic labeling of RGB-D scenes is crucial to many intelligent applications
including perceptual robotics. It generates pixelwise and fine-grained label
maps from simultaneously sensed photometric (RGB) and depth channels. This
paper addresses this problem by i) developing a novel Long Short-Term Memorized
Context Fusion (LSTM-CF) Model that captures and fuses contextual information
from multiple channels of photometric and depth data, and ii) incorporating
this model into deep convolutional neural networks (CNNs) for end-to-end
training. Specifically, contexts in photometric and depth channels are,
respectively, captured by stacking several convolutional layers and a long
short-term memory layer; the memory layer encodes both short-range and
long-range spatial dependencies in an image along the vertical direction.
Another long short-term memorized fusion layer is set up to integrate the
contexts along the vertical direction from different channels, and perform
bi-directional propagation of the fused vertical contexts along the horizontal
direction to obtain true 2D global contexts. At last, the fused contextual
representation is concatenated with the convolutional features extracted from
the photometric channels in order to improve the accuracy of fine-scale
semantic labeling. Our proposed model has set a new state of the art, i.e.,
48.1% and 49.4% average class accuracy over 37 categories (2.2% and 5.4%
improvement) on the large-scale SUNRGBD dataset and the NYUDv2dataset,
respectively.


title:
Fronthaul Compression and Transmit Beamforming Optimization for
  Multi-Antenna Uplink C-RAN

abstract:
  This paper considers the joint fronthaul compression and transmit beamforming
design for the uplink cloud radio access network (C-RAN), in which
multi-antenna user terminals communicate with a cloud-computing based
centralized processor (CP) through multi-antenna base-stations (BSs) serving as
relay nodes. A compress-and-forward relaying strategy, named the VMAC scheme,
is employed, in which the BSs can either perform single-user compression or
Wyner-Ziv coding to quantize the received signals and send the quantization
bits to the CP via capacity-limited fronthaul links; the CP performs successive
decoding with either successive interference cancellation (SIC) receiver or
linear minimum-mean-square-error (MMSE) receiver. Under this setup, this paper
investigates the joint optimization of the transmit beamformers at the users
and the quantization noise covariance matrices at the BSs for maximizing the
network utility. A novel weighted minimum-mean-square-error successive convex
approximation (WMMSE-SCA) algorithm is first proposed for maximizing the
weighted sum rate under the user transmit power and fronthaul capacity
constraints with single-user compression. Assuming a heuristic decompression
order, the proposed algorithm is then adapted for optimizing the transmit
beamforming and fronthaul compression under Wyner-Ziv coding. This paper also
proposes a low-complexity separate design consisting of optimizing transmit
beamformers for the Gaussian vector multiple-access channel along with
per-antenna quantizers with uniform quantization noise levels across the
antennas at each BS. Numerical results show that with optimized beamforming and
fronthaul compression, C-RAN can significantly outperform conventional cellular
networks. Furthermore, the low complexity separate design already performs very
close to the optimized joint design in regime of practical interest.


title:
Equation of state and transition temperatures in the quark-hadron hybrid
  model

abstract:
  We analyze the equation of state of 2+1 flavor lattice QCD at zero baryon
density by constructing the simple quark-hadron hybrid model that has both
quark and hadron components simultaneously. We calculate hadron and quark
contribution separately and parameterizing those to match with LQCD data.
Lattice data on the equation of state are decomposed into hadron and quark
components by using the model. The transition temperature is defined by the
temperature at which the hadron component is equal to the quark one in the
equation of state. The transition temperature thus obtained is about 215 MeV
and somewhat higher than the chiral and the deconfinement pseudocritical
temperatures defined by the temperature at which the susceptibility or the
absolute value of the derivative of the order parameter with respect to
temperature becomes maximum.


title: Global gravitational anomalies and transport

abstract:
  We investigate the constraints imposed by global gravitational anomalies on
parity odd induced transport coefficients in even dimensions for theories with
chiral fermions, gravitinos and self dual tensors. The $\eta$-invariant for the
large diffeomorphism corresponding to the $T$ transformation on a torus
constraints the coefficients in the thermal effective action up to mod 2. We
show that the result obtained for the parity odd transport for gravitinos using
global anomaly matching is consistent with the direct perturbative calculation.
In $d=6$ we see that the second Pontryagin class in the anomaly polynomial does
not contribute to the $\eta$-invariant which provides a topological explanation
of this observation in the `replacement rule'. We then perform a direct
perturbative calculation for the contribution of the self dual tensor in $d=6$
to the parity odd transport coefficient using the Feynman rules proposed by
Gaum\'{e} and Witten. The result for the transport coefficient agrees with that
obtained using matching of global anomalies.


title: Unfoldings of the Cube

abstract:
  Just how many different connected shapes result from slicing a cube along
some of its edges and unfolding it into the plane? In this article we answer
this question by viewing the cube both as a surface and as a graph of vertices
and edges. This dual perspective invites an interplay of geometric, algebraic,
and combinatorial techniques. The initial observation is that a cutting pattern
which unfolds the cubical surface corresponds to a spanning tree of the cube
graph. The Matrix-Tree theorem can be used to calculate the number of spanning
trees in a connected graph, and thus allows us to compute the number of ways to
unfold the cube. Since two or more spanning trees may yield the same unfolding
shape, Burnside's lemma is required to count the number of incongruent
unfoldings. Such a count can be an arduous task. Here we employ a combination
of elementary algebraic and geometric techniques to bring the problem within
the range of simple hand calculations.


title:
A Search/Crawl Framework for Automatically Acquiring Scientific
  Documents

abstract:
  Despite the advancements in search engine features, ranking methods,
technologies, and the availability of programmable APIs, current-day
open-access digital libraries still rely on crawl-based approaches for
acquiring their underlying document collections. In this paper, we propose a
novel search-driven framework for acquiring documents for scientific portals.
Within our framework, publicly-available research paper titles and author names
are used as queries to a Web search engine. Next, research papers and sources
of research papers are identified from the search results using accurate
classification modules. Our experiments highlight not only the performance of
our individual classifiers but also the effectiveness of our overall
Search/Crawl framework. Indeed, we were able to obtain approximately 0.665
million research documents through our fully-automated framework using about
0.076 million queries. These prolific results position Web search as an
effective alternative to crawl methods for acquiring both the actual documents
and seed URLs for future crawls.


title:
Expressive Completeness of Existential Rule Languages for Ontology-based
  Query Answering

abstract:
  Existential rules, also known as data dependencies in Databases, have been
recently rediscovered as a promising family of languages for Ontology-based
Query Answering. In this paper, we prove that disjunctive embedded dependencies
exactly capture the class of recursively enumerable ontologies in
Ontology-based Conjunctive Query Answering (OCQA). Our expressive completeness
result does not rely on any built-in linear order on the database. To establish
the expressive completeness, we introduce a novel semantic definition for OCQA
ontologies. We also show that neither the class of disjunctive tuple-generating
dependencies nor the class of embedded dependencies is expressively complete
for recursively enumerable OCQA ontologies.


title:
Topologically induced fractional Hall steps in the integer quantum Hall
  regime of $MoS_2$

abstract:
  The quantum magnetotransport properties of a monolayer of molybdenum
disulfide are derived using linear response theory. Especially, the effect of
topological terms on longitudinal and Hall conductivity is analyzed. The Hall
conductivity exhibits fractional steps in the integer quantum Hall regime.
Further complete spin and valley polarization of the longitudinal conductivity
is seen in presence of these topological terms. Finally, the Shubnikov-de Hass
oscillations are suppressed or enhanced contingent on the sign of these
topological terms.


title:
Forecasting Volatility in Indian Stock Market using Artificial Neural
  Network with Multiple Inputs and Outputs

abstract:
  Volatility in stock markets has been extensively studied in the applied
finance literature. In this paper, Artificial Neural Network models based on
various back propagation algorithms have been constructed to predict volatility
in the Indian stock market through volatility of NIFTY returns and volatility
of gold returns. This model considers India VIX, CBOE VIX, volatility of crude
oil returns (CRUDESDR), volatility of DJIA returns (DJIASDR), volatility of DAX
returns (DAXSDR), volatility of Hang Seng returns (HANGSDR) and volatility of
Nikkei returns (NIKKEISDR) as predictor variables. Three sets of experiments
have been performed over three time periods to judge the effectiveness of the
approach.


title:
On the Cauchy problem of a degenerate parabolic-hyperbolic PDE with
  L\'{e}vy noise

abstract:
  In this article we deal with stochastic perturbation of degenerate parabolic
partial differential equations (PDEs). The particular emphasise is on analysing
the effect of multiplicative L\'{e}vy noise to such problems and establishing
wellposedness by developing a suitable weak entropy solution framework. The
proof of existence is based on the vanishing viscosity technique. The
uniqueness is settled by interpreting Kruzkov's doubling technique in the
presence noise.


title:
Fermi Study of 5-300 GeV emission from the high-mass pulsar binary PSR
  B1259-63/LS 2883

abstract:
  We report the results from our detailed analysis of the Fermi Large Area
Telescope (LAT) data for the pulsar binary PSR B1259-63/LS 2883. During the GeV
flares that occurred when the pulsar was in the periastron passages, we have
detected a 5--300 GeV component at $\simeq 5\sigma$ in emission from the
binary. The detection verifies the presence of the component that has been
marginally found in the previous studies of the binary. Furthermore, we have
discovered that this component was present even in the quiescent state of the
binary, specifically the mean anomaly phase 0.7--0.9. The component can be
described by a power law with photon index $\Gamma\sim 1.4$, and the flux in
the flares is approximately one order of magnitude higher than that in
quiescence. We discuss the origin of this component. It likely arises from the
inverse-Compton process: high-energy particles from the shock, due to the
interaction between the winds from the pulsar and massive companion, scatter
the seed photons from the companion to GeV/TeV energies. Based on this
scenario, model fits to the broad-band X-ray--to--TeV spectra of the binary in
the flaring and quiescent states are provided.


title:
From liquid crystal models to the guiding-center theory of magnetized
  plasmas

abstract:
  Upon combining Northrop's picture of charged particle motion with modern
liquid crystal theories, this paper provides a new description of guiding
center dynamics (to lowest order). This new perspective is based on a rotation
gauge field (gyrogauge) that encodes rotations around the magnetic field. In
liquid crystal theory, an analogue rotation field is used to encode the
rotational state of rod-like molecules. Instead of resorting to sophisticated
tools (e.g. Hamiltonian perturbation theory and Lie series expansions) that
still remain essential in higher-order gyrokinetics, the present approach
combines the WKB method with a simple kinematical ansatz, which is then
replaced into the charged particle Lagrangian. The latter is eventually
averaged over the gyrophase to produce Littlejohn's guiding-center equations. A
crucial role is played by the vector potential for the gyrogauge field. A
similar vector potential is related to liquid crystal defects and is known as
`wryness tensor' in Eringen's micropolar theory.


title:
On the global existence of spherically symmetric hairy black holes and
  solitons in anti-de Sitter Einstein-Yang-Mills theories with compact
  semisimple gauge groups

abstract:
  We investigate the existence of black hole and soliton solutions to four
dimensional, anti-de Sitter (adS), Einstein-Yang-Mills theories with general
semisimple connected and simply connected gauge groups, concentrating on the
so-called "regular" case. We here generalise results for the asymptotically
flat case, and compare our system with similar results from the well-researched
adS $\mathfrak{su}(N)$ system. We find the analysis differs from the
asymptotically flat case in some important ways: the biggest difference is that
for $\Lambda<0$, solutions are much less constrained as $r\rightarrow\infty$,
making it possible to prove the existence of global solutions to the field
equations in some neighbourhood of existing trivial solutions, and in the limit
of $|\Lambda|\rightarrow\infty$. In particular, we can identify non-trivial
solutions where the gauge field functions have no zeroes, which in the
$\mathfrak{su}(N)$ case proved important to stability.


title:
Ferro-deformation at the nuclear system with protons, Z = 20 and
  neutrons, N = 40: 60Ca

abstract:
  We present a possibility that the system with Z = 20, N = 40, 60Ca, has a
large deformation, even though it has both proton and neutron magic numbers,
symbolizing a spherical nucleus. This large deformation corresponds to the
so-called ferro-deformation that occurs at the particular critical points over
the nuclear chart. By comparisons with the ferra-deformation at the critical
point Z = 40, N = 64 [arXiv:1604.02786], we draw a conclusion that shape phase
transitions should occur at Z = 18 or 20 when N = 36 to 38, which leads to a
ferro-deformation at the critical points of Z = 18 or 20, N = 40; 58Ar, 60Ca.
We explain the shape phase transition in terms of isospin dependent
spin-orbital interactions between neutrons in the f5/2 orbital and protons in
the f7/2 orbital. We find a universal behavior over the nuclear chart for
yielding the ferro-deformation such that; Z = 64, N = 104, Z = 40, N = 64, and
Z = 20, N = 40, respectively. This feature is linked to concept of the
neutron(n)-proton(p)interaction in spin-orbital couplings such that;
nh9/2-ph11/2, ng7/2-pg9/2, and nf5/2-pf7/2, respectively. It is suggested that
triple shape coexistence would be possible in the Z = 20, N = 36, 56Ca, and the
Z = 18, N = 36, 54Ar, where the ferro-deformation is expected to be built on
the second 0+ state. The predicted level schemes for 52Ar, 54Ar, 56Ar, 56Ca,
58Ca, and 60Ca are presented.


title:
On sets of marked once-holed tori allowing holomorphic mappings into
  Riemann surfaces with marked handle

abstract:
  In our previous work, for a given Riemann surface $Y_0$ with marked handle,
we investigated geometric properties of the set of marked once-holed tori $X$
allowing holomorphic mappings of $X$ into $Y_0$. It turned out that it is a
closed domain with Lipschitz boundary. In the present paper we show that the
boundary is never smooth. Also, we evaluate the critical extremal length for
the existence of holomorphic mappings in terms of hyperbolic lengths.


title: Using Clustering Method to Understand Indian Stock Market Volatility

abstract:
  In this paper we use Clustering Method to understand whether stock market
volatility can be predicted at all, and if so, when it can be predicted. The
exercise has been performed for the Indian stock market on daily data for two
years. For our analysis we map number of clusters against number of variables.
We then test for efficiency of clustering. Our contention is that, given a
fixed number of variables, one of them being historic volatility of NIFTY
returns, if increase in the number of clusters improves clustering efficiency,
then volatility cannot be predicted. Volatility then becomes random as, for a
given time period, it gets classified in various clusters. On the other hand,
if efficiency falls with increase in the number of clusters, then volatility
can be predicted as there is some homogeneity in the data. If we fix the number
of clusters and then increase the number of variables, this should have some
impact on clustering efficiency. Indeed if we can hit upon, in a sense, an
optimum number of variables, then if the number of clusters is reasonably
small, we can use these variables to predict volatility. The variables that we
consider for our study are volatility of NIFTY returns, volatility of gold
returns, India VIX, CBOE VIX, volatility of crude oil returns, volatility of
DJIA returns, volatility of DAX returns, volatility of Hang Seng returns and
volatility of Nikkei returns. We use three clustering algorithms namely Kernel
K-Means, Self Organizing Maps and Mixture of Gaussian models and two internal
clustering validity measures, Silhouette Index and Dunn Index, to assess the
quality of generated clusters.


title: Status Report of the GERDA Phase II Startup

abstract:
  The GERmanium Detector Array GERDA experiment, located at the Laboratori
Nazionali del Gran Sasso (LNGS) of INFN, searches for $0\nu\beta\beta$ of
$^{76}$Ge. Germanium diodes enriched to $\sim 86~\%$ in the double beta emitter
$^{76}$Ge ($^{enr}$Ge) are exposed being both source and detectors of
$0\nu\beta\beta$ decay. Neutrinoless double beta decay is considered a powerful
probe to address still open issues in the neutrino sector of the (beyond)
Standard Model of particle Physics. Since 2013, just after the completion of
the first part of its experimental program (Phase I), the GERDA setup has been
upgraded to perform its next step in the $0\nu\beta\beta$ searches (Phase II).
Phase II aims to reach a sensitivity to the $0\nu\beta\beta$ decay half-life
larger than $10^{26}~$yr in about 3 years of physics data taking. This exposing
a detector mass of about $35~$kg of $^{enr}$Ge and with a background index of
about $10^{-3}~$cts/(keV$\cdot$kg$\cdot$yr). One of the main new
implementations is the liquid argon scintillation light read-out, to veto those
events that only partially deposit their energy both in Ge and in the
surrounding LAr. In this paper the GERDA Phase II expected goals, the upgrade
work and few selected features from the 2015 commissioning and 2016 calibration
runs will be presented. The main Phase I achievements will be also reviewed.


title:
Reproducing kernel Hilbert spaces and variable metric algorithms in PDE
  constrained shape optimisation

abstract:
  In this paper we investigate and compare different gradient algorithms
designed for the domain expression of the shape derivative. Our main focus is
to examine the usefulness of kernel reproducing Hilbert spaces for PDE
constrained shape optimisation problems. We show that radial kernels provide
convenient formulas for the shape gradient that can be efficiently used in
numerical simulations. The shape gradients associated with radial kernels
depend on a so called smoothing parameter that allows a smoothness adjustment
of the shape during the optimisation process. Besides, this smoothing parameter
can be used to modify the movement of the shape. The theoretical findings are
verified in a number of numerical experiments.


title:
Effective inter-symbol interference mitigation with a limited amount of
  enzymes in molecular communications

abstract:
  In molecular communication via diffusion (MCvD), the inter-symbol
interference (ISI) is a well known severe problem that deteriorates both data
rates and link reliability. ISI mainly occurs due to the slow and highly random
propagation of the messenger molecules, which causes the emitted molecules from
the previous symbols to interfere with molecules from the current symbol. An
effective way to mitigate the ISI is using enzymes to degrade undesired
molecules. Prior work on ISI mitigation by enzymes has assumed an infinite
amount of enzymes randomly distributed around the molecular channel. Taking a
different approach, this paper assumes an MCvD channel with a limited amount of
enzymes. The main question this paper addresses is how to deploy these enzymes
in an effective structure so that ISI mitigation is maximized. To find an
effective MCvD channel environment, this study considers optimization of the
shape of the transmitter node, the deployment location and structure, the size
of the enzyme deployed area, and the half-lives of the enzymes. It also
analyzes the dependence of the optimum size of the enzyme area on the distance
and half-life.


title: Proof of a recent conjecture of Z.-W. Sun

abstract:
  The polynomials $d_n(x)$ are defined by \begin{align*} d_n(x) &=
\sum_{k=0}^n{n\choose k}{x\choose k}2^k. \end{align*} We prove that, for any
prime $p$, the following congruences hold modulo $p$: \begin{align*}
\sum_{k=0}^{p-1}\frac{{2k\choose k}}{4^k} d_k\left(-\frac{1}{4}\right)^2
&\equiv \begin{cases} 2(-1)^{\frac{p-1}{4}}x,&\text{if $p=x^2+y^2$ with
$x\equiv 1\pmod{4}$,} 0,&\text{if $p\equiv 3\pmod{4}$,} \end{cases} [5pt]
\sum_{k=0}^{p-1}\frac{{2k\choose k}}{4^k} d_k\left(-\frac{1}{6}\right)^2
&\equiv 0, \quad\text{if $p>3$,} [5pt] \sum_{k=0}^{p-1}\frac{{2k\choose
k}}{4^k} d_k\left(\frac{1}{4}\right)^2 &\equiv \begin{cases} 0,&\text{if
$p\equiv 1\pmod{4}$,} (-1)^{\frac{p+1}{4}}{\frac{p-1}{2}\choose
\frac{p-3}{4}},&\text{if $p\equiv 3\pmod{4}$.} \end{cases}
\sum_{k=0}^{p-1}\frac{{2k\choose k}}{4^k} d_k\left(\frac{1}{6}\right)^2 &\equiv
0, \quad\text{if $p>5$.} \end{align*} The $p\equiv 3\pmod{4}$ case of the first
one confirms a conjecture of Z.-W. Sun, while the second one confirms a special
case of another conjecture of Z.-W. Sun.


title:
Tight lower bounds on the matching number in a graph with given maximum
  degree

abstract:
  Let $k \geq 3$. We prove the following three bounds for the matching number,
$\alpha'(G)$, of a graph, $G$, of order $n$ size $m$ and maximum degree at most
$k$.
  If $k$ is odd, then $\alpha'(G) \ge \left( \frac{k-1}{k(k^2 - 3)} \right) n
\, + \, \left( \frac{k^2 - k - 2}{k(k^2 - 3)} \right) m \, - \,
\frac{k-1}{k(k^2 - 3)}$. If $k$ is even, then $\alpha'(G) \ge \frac{n}{k(k+1)}
\, + \, \frac{m}{k+1} - \frac{1}{k}$. If $k$ is even, then $\alpha'(G) \ge
\left( \frac{k+2}{k^2+k+2} \right) m \, - \, \left( \frac{k-2}{k^2+k+2} \right)
n \, - \frac{k+2}{k^2+k+2}$.
  In this paper we actually prove a slight strengthening of the above for which
the bounds are tight for essentially all densities of graphs.
  The above three bounds are in fact powerful enough to give a complete
description of the set $L_k$ of pairs $(\gamma,\beta)$ of real numbers with the
following property. There exists a constant $K$ such that $\alpha'(G) \geq
\gamma n + \beta m - K$ for every connected graph $G$ with maximum degree at
most~$k$, where $n$ and $m$ denote the number of vertices and the number of
edges, respectively, in $G$. We show that $L_k$ is a convex set. Further, if
$k$ is odd, then $L_k$ is the intersection of two closed half-spaces, and there
is exactly one extreme point of $L_k$, while if $k$ is even, then $L_k$ is the
intersection of three closed half-spaces, and there are precisely two extreme
points of $L_k$.


title:
The numbers of repeated palindromes in the Fibonacci and Tribonacci
  sequences

abstract:
  The Fibonacci sequence $\mathbb{F}$ is the fixed point beginning with $a$ of
morphism $\sigma(a,b)=(ab,a)$. Since $\mathbb{F}$ is uniformly recurrent, each
factor $\omega$ appears infinite many times in the sequence which is arranged
as $\omega_p$ $(p\ge 1)$. Here we distinguish $\omega_p\neq\omega_q$ if $p\neq
q$. In this paper, we give algorithm for counting the number of repeated
palindromes in $\mathbb{F}[1,n]$ (the prefix of $\mathbb{F}$ of length $n$).
That is the number of the pairs $(\omega, p)$, where $\omega$ is a palindrome
and $\omega_p\prec\mathbb{F}[1,n]$. We also get explicit expressions for some
special $n$ such as $n=f_m$ (the $m$-th Fibonacci number). The similar results
are also given to the Tribonacci sequence, the fixed point beginning with $a$
of morphism $\tau(a,b,c)=(ab,ac,a)$.


title: Quantum Geo-Encryption

abstract:
  In this work we introduce the concept of quantum geo-encryption - a protocol
that invokes direct quantum encryption of messages coupled to quantum location
monitoring of the intended receiver. By obfuscating the quantum information
required by both the decrypting process and the location verification process,
a communication channel is created in which the encrypted data can only be
decrypted at a specific geographic locale. Classical wireless communications
can be invoked to unlock the quantum encryption process thereby allowing for
any deployment scenario regardless of the channel conditions. Quantum
geo-encryption can also be used to realize quantum-computing instructions that
can only be implemented at a specific location, and allow for a specified
geographical data-route through a distributed network. Here we consider the
operational aspects of quantum geo-encryption in generic Rician channels,
demonstrating that the likelihood of a successful spoofing attack approaches
zero as the adversary moves away from the allowed decrypting location. The work
introduced here resolves a long-standing quest to directly deliver information
which can only be decrypted at a given location free of assumptions on the
physical security of a receiver.


title: Impact of Knowledge on Election Time in Anonymous Networks

abstract:
  Leader election is one of the basic problems in distributed computing. For
anonymous networks, the task of leader election is formulated as follows: every
node v of the network must output a simple path, which is coded as a sequence
of port numbers, such that all these paths end at a common node, the leader. In
this paper, we study deterministic leader election in arbitrary anonymous
networks. It is well known that leader election is impossible in some networks,
regardless of the allocated amount of time, even if nodes know the map of the
network. However, even in networks in which it is possible to elect a leader
knowing the map, the task may be still impossible without any knowledge,
regardless of the allocated time. On the other hand, for any network in which
leader election is possible knowing the map, there is a minimum time, called
the election index, in which this can be done. Informally, the election index
of a network is the minimum depth at which views of all nodes are distinct. Our
aim is to establish tradeoffs between the allocated time $\tau$ and the amount
of information that has to be given a priori to the nodes to enable leader
election in time $\tau$ in all networks for which leader election in this time
is at all possible. Following the framework of algorithms with advice, this
information is provided to all nodes at the start by an oracle knowing the
entire network. The length of this string (its number of bits) is called the
size of advice. For a given time $\tau$ allocated to leader election, we give
upper and lower bounds on the minimum size of advice sufficient to perform
leader election in time $\tau$. We focus on the two sides of the time spectrum
and give tight (or almost tight) bounds on the minimum size of advice for these
extremes. We also show that constant advice is not sufficient for leader
election in all graphs, regardless of the allocated time.


title:
Empirical study of PROXTONE and PROXTONE$^+$ for Fast Learning of Large
  Scale Sparse Models

abstract:
  PROXTONE is a novel and fast method for optimization of large scale
non-smooth convex problem \cite{shi2015large}. In this work, we try to use
PROXTONE method in solving large scale \emph{non-smooth non-convex} problems,
for example training of sparse deep neural network (sparse DNN) or sparse
convolutional neural network (sparse CNN) for embedded or mobile device.
PROXTONE converges much faster than first order methods, while first order
method is easy in deriving and controlling the sparseness of the solutions.
Thus in some applications, in order to train sparse models fast, we propose to
combine the merits of both methods, that is we use PROXTONE in the first
several epochs to reach the neighborhood of an optimal solution, and then use
the first order method to explore the possibility of sparsity in the following
training. We call such method PROXTONE plus (PROXTONE$^+$). Both PROXTONE and
PROXTONE$^+$ are tested in our experiments, and which demonstrate both methods
improved convergence speed twice as fast at least on diverse sparse model
learning problems, and at the same time reduce the size to 0.5\% for DNN
models. The source of all the algorithms is available upon request.


title: Holographic Schwinger Effect and Chiral condensate in SYM Theory

abstract:
  We study the instability, for the supersymmetric Yang-Mills (SYM) theories,
caused by the external electric field through the imaginary part of the action
of the D7 probe brane, which is embedded in the background of type IIB theory.
This instability is related to the Schwinger effect, namely to the quark pair
production due to the external electric field, for the $SU(N_c)$ SYM theories.
In this holographic approach, it is possible to calculate the Schwinger effect
for various phases of the theories. Here we give the calculation for ${\cal
N}=2$ SYM theory and the analysis is extended to the finite temperature
deconfinement and the zero temperature confinement phases of the Yang-Mills
(YM) theory. By comparing the obtained production rates with the one of the
supersymmetric case, the dynamical quark mass is estimated and we find how it
varies with the chiral condensate. Based on this analysis, we give a
speculation on the extension of the Nambu-Jona-Lasinio model to the finite
temperature YM theory, and four fermi coupling is evaluated in the confinement
theory.


title:
Pleomorphic structural imperfections caused by pulsed Bi-implantation in
  the bulk and thin-film morphologies of TiO2

abstract:
  The results of combined experimental and theoretical study of substitutional
and clustering effects in Bi-doped TiO2 hosts (bulk and thin-film morphologies)
are presented. Bi-doping of the bulk and thin-film titanium dioxide was made
with help of pulsed ion-implantation (E(Bi+) = 30 keV, D = 1 * 1017 cm-2)
without posterior tempering. The X-ray photoelectron spectroscopy (XPS)
qualification (core-levels and valence bands) and Density-Functional Theory
(DFT) calculations were employed in order to study the electronic structure of
Bi-ion implanted TiO2 samples. According to XPS data obtained and DFT
calculations, the Bi -> Ti cation substitution occurs in Bi-implanted bulk
TiO2, whereas in the thin-film morphology of TiO2:Bi the Bi-atoms have
metal-like clusters segregation tendency. Based on the combined XPS and DFT
considerations the possible reasons and mechanism for the observed effects are
discussed. It is believed that established peculiarities of bismuth embedding
into employed TiO2 hosts are mostly the sequence of pleomorphic origin for the
formed "bismuth-oxygen" chemical bonding.


title:
Most Likely Separation of Intensity and Warping Effects in Image
  Registration

abstract:
  This paper introduces a class of mixed-effects models for joint modeling of
spatially correlated intensity variation and warping variation in 2D images.
Spatially correlated intensity variation and warp variation are modeled as
random effects, resulting in a nonlinear mixed-effects model that enables
simultaneous estimation of template and model parameters by optimization of the
likelihood function. We propose an algorithm for fitting the model which
alternates estimation of variance parameters and image registration. This
approach avoids the potential estimation bias in the template estimate that
arises when treating registration as a preprocessing step. We apply the model
to datasets of facial images and 2D brain magnetic resonance images to
illustrate the simultaneous estimation and prediction of intensity and warp
effects.


title:
Chemistry in Disks X: The Molecular Content of Proto-planetary Disks in
  Taurus

abstract:
  (abridged) We used the IRAM 30-m to perform a sensitive wideband survey of 30
protoplanetary disks in the Taurus Auriga region. We simultaneously observed
HCO$^+$(3-2), HCN(3-2), C$_2$H(3-2), CS(5-4), and two transitions of SO. We
combine the results with a previous survey which observed $^{13}$CO (2-1),
CN(2-1), two o-H$_2$CO lines and one of SO. We use available interferometric
data to derive excitation temperatures of CN and C$_2$H in several sources. We
determine characteristic sizes of the gas disks and column densities of all
molecules using a parametric power-law disk model. Our study is mostly
sensitive to molecules at 200-400 au from the stars. We compare the derived
column densities to the predictions of an extensive gas-grain chemical disk
model, under conditions representative of T Tauri disks. This survey provides
20 new detections of HCO$^+$ in disks, 18 in HCN, 11 in C$_2$H, 8 in CS and 4
in SO. HCO$^+$ is detected in almost all sources, and its J=3-2 line is
essentially optically thick, providing good estimates of the disk radii. The
other transitions are (at least partially) optically thin. Variations of the
column density ratios do not correlate with any specific property of the star
or disk. Disks around Herbig Ae stars appear less rich in molecules than those
around T Tauri stars, although the sample remains small. SO is only found in
the (presumably younger) embedded objects, perhaps reflecting an evolution of
the S chemistry due to increasing depletion with time. Overall, the molecular
column densities, and in particular the CN/HCN and CN/C$_2$H ratios, are well
reproduced by gas-grain chemistry in cold disks. This study provides a census
of simple molecules in disks of radii $> 200-300$ au. Extending that to smaller
disks, or searching for less abundant or more complex molecules requires a much
more sensitive facility, i.e. NOEMA and ALMA.


title: Non-Euclidean Fourier inversion on super-hyperbolic space

abstract:
  For the super-hyperbolic space in any dimension, we introduce the
non-Euclidean Helgason--Fourier transform. We prove an inversion formula
exhibiting residue contributions at the poles of the Harish-Chandra c-function,
signalling discrete parts in the spectrum. The proof is based on a detailed
study of the spherical superfunctions, using recursion relations and
localization techniques to normalize them precisely, careful estimates of their
derivatives, and a rigorous analysis of the boundary terms appearing in the
polar coordinate expression of the invariant integral


title:
How to reveal metastable skyrmionic spin structures by spin-polarized
  scanning tunneling microscopy

abstract:
  We predict the occurrence of metastable skyrmionic spin structures such as
antiskyrmions and higher-order skyrmions in ultra-thin transition-metal films
at surfaces using Monte Carlo simulations based on a spin Hamiltonian
parametrized from density functional theory calculations. We show that such
spin structures will appear with a similar contrast in spin-polarized scanning
tunneling microscopy (SP-STM) images. Both skyrmions and antiskyrmions display
a circular shape for out-of-plane magnetized tips and a two-lobe butterfly
contrast for in-plane tips. An unambiguous distinction can be achieved by
rotating the tip magnetization direction without requiring the information of
all components of the magnetization.


title:
The effect of multilayer ice chemistry on gas-phase deuteration in
  starless cores

abstract:
  Aims. We aim to investigate whether a multilayer ice model can be as
successful as a bulk ice model in reproducing the observed abundances of
various deuterated gas-phase species toward starless cores. Methods. We
calculate abundances for various deuterated species as functions of time
adopting fixed physical conditions. We also estimate abundance gradients by
adopting a modified Bonnor-Ebert sphere as a core model. In the multilayer ice
scenario, we consider desorption from one or several monolayers on the surface.
Results. We find that the multilayer model predicts abundances of $\rm DCO^+$
and $\rm N_2D^+$ that are about an order of magnitude lower than observed,
caused by the trapping of CO and $\rm N_2$ into the grain mantle. As a result
of the mantle trapping, deuteration efficiency in the gas phase increases and
we find stronger deuterium fractionation in ammonia than what has been
observed. Another distinguishing feature of the multilayer model is that $\rm
D_3^+$ becomes the main deuterated ion at high density. The bulk ice model is
generally easily reconciled with observations. Conclusions. Our results
underline that more theoretical and experimental work is needed to understand
the composition and morphology of interstellar ices, and the desorption
processes that can act on them. With the current constraints, the bulk ice
model appears to be better in reproducing observations than the multilayer ice
model. According to our results, the $\rm H_2D^+$ to $\rm N_2D^+$ abundance
ratio is higher than 100 in the multilayer model, while only a few $\times$ 10
in the bulk model, and so observations of this ratio could provide information
on the ice morphology in starless cores. Observations of the abundance of $\rm
D_3^+$ compared to $\rm H_2D^+$ and $\rm D_2H^+$ would provide additional
constraints for the models.


title:
On the box-counting dimension of potential singular set for suitable
  weak solutions to the 3D Navier-Stokes equations

abstract:
  In this paper, we are concerned with the upper box-counting dimension of the
set of possible singular points in space-time of suitable weak solutions to the
3D Navier-Stokes equations. By taking full advantage of the pressure $\Pi$ in
terms of $\nabla \Pi$ in equations, we show that this upper box dimension is at
most $135/104(\approx1.30)$, which improves the known upper box-counting
dimension $95/63(\approx1.51)$ in Koh et al. [9, J. Differential Equations,
261: 3137--3148, 2016], $45/29(\approx1.55)$ in Kukavica et al. [11,
Nonlinearity 25: 2775-2783, 2012] and $135/82(\approx1.65)$ in Kukavica [10,
Nonlinearity 22: 2889-2900, 2009].


title: Fingerprints of Majorana fermions in spin-resolved subgap spectroscopy

abstract:
  When a strongly correlated quantum dot is tunnel-coupled to a superconductor,
it leads to the formation of Shiba bound states inside the superconducting gap.
They have been measured experimentally in a superconductor-quantum dot-normal
lead setup. Side coupling the quantum dot to a topological superconducting wire
that supports Majorana bound states at its ends, drastically affects the
structure of the Shiba states and induces supplementary in-gap states. The
anomalous coupling between the Majorana bound states and the quantum dot gives
rise to a characteristic imbalance in the spin resolved spectral functions for
the dot operators. These are clear fingerprints for the existence of Majorana
fermions and they can be detected experimentally in transport measurements. In
terms of methods employed, we have used analytical approaches combined with the
numerical renormalization group approach.


title: Pseudosingularity in the eigenvalue integral equations

abstract:
  The reliability is of the most importance when employing a numerical method
to solve the eigenvalue integral equations. In this paper, we present one type
of particular singularities (pseudosingularities) existing in eigenvalue
integral equations which will impair even destroy the reliability of the
numerical solutions in an implicit way. Two odd phenomena emerging in the
numerical eigenvalues and the corresponding eigenfunctions are reviewed. And
the relations between the pseudosingularities, the odd phenomena and the
reliability of the obtained numerical results are discussed.


title: Probing classically conformal $B-L$ model with gravitational waves

abstract:
  We study the cosmological history of the classical conformal $B-L$ gauge
extension of the standard model, in which the physical scales are generated via
the Coleman-Weinberg-type symmetry breaking. Especially, we consider the
thermal phase transition of the U$(1)_{B-L}$ symmetry in the early universe and
resulting gravitational-wave production. Due to the classical conformal
invariance, the phase transition tends to be a first-order one with
ultra-supercooling, which enhances the strength of the produced gravitational
waves. We show that, requiring (1) U$(1)_{B-L}$ is broken after the reheating,
(2) the $B-L$ gauge coupling does not blow up below the Planck scale, (3) the
thermal phase transition completes in almost all the patches in the universe,
the gravitational wave spectrum can be as large as $\Omega_{\rm GW} \sim
10^{-8}$ at the frequency $f \sim 0.01$-$1$Hz for some model parameters, and a
vast parameter region can be tested by future interferometer experiments such
as eLISA, LISA, BBO and DECIGO.


title: Tagging $b$ quarks at extreme energies without tracks

abstract:
  We describe a new hit-based $b$-tagging technique for high energy jets and
study its performance with a Geant4-based simulation. The technique uses the
fact that at sufficiently high energy a B meson or baryon can live long enough
to traverse the inner layers of pixel detectors such as those in the ATLAS,
ALICE, or CMS experiments prior to decay. By first defining a "jet" via the
calorimeter, and then counting hits within that jet between pixel layers at
increasing radii, we show it is possible to identify jets that contain
$b$-quarks by detecting a jump in the number of hits. We show that the
technique maintains its efficiency at energies beyond the range of conventional
$b$-taggers.


title: Joint DOA and Frequency Estimation with Sub-Nyquist Sampling

abstract:
  In this paper, to jointly estimate the frequency and the
direction-of-arrival(DOA) of the narrowband far-field signals, a novel array
receiver architecture is presented by the concept of the sub-Nyquist sampling
techniques. In particular, our contribution is threefold. i) First, we propose
a time-space union signal reception model for receiving array signals, where
the sub-Nyquist sampling techniques and arbitrary array geometries are employed
to decrease the time-domain sampling rate and improve the DOA estimation
accuracy. A better joint estimation is obtained in the higher time-space union
space. ii) Second, two joint estimation algorithms are proposed for the
receiving model. One is based on a trilinear decomposition from the third-order
tensor theory and the other is based on subspace decomposition. iii) Third, we
derive the corresponding Cram\'er\text{-}Rao Bound (CRB) for frequency and DOA
estimates. In the case of the branch number of our architecture is equal to the
reduction factor of the sampling rate, it is observed that the CRB is robust in
terms of the number of signals, while the CRB based on the Nyquist sampling
scheme will increase with respect to the number of signals. In addition, the
new steer vectors of the union time-space model are completely uncorrelated
under the limited number of sensors, which improves the estimation performance.
Furthermore, the simulation results demonstrate that our estimates via the
receiver architecture associated with the proposed algorithms closely match the
CRB according to the noise levels, the branch number and the source number as
well.


title:
Periodic homogenization of non-local operators with a convolution type
  kernel

abstract:
  The paper deals with homogenization problem for a non-local linear operator
with a kernel of convolution type in a medium with a periodic structure. We
consider the natural diffusive scaling of this operator and study the limit
behaviour of the rescaled operators as the scaling parameter tends to 0. More
precisely we show that in the topology of resolvent convergence the family of
rescaled operators converges to a second order elliptic operator with constant
coefficients. We also prove the convergence of the corresponding semigroups
both in $L^2$ space and the space of continuous functions, and show that for
the related family of Markov processes the invariance principle holds.


title: Chern insulator with large Chern numbers. Chiral Majorana fermion liquid

abstract:
  In the framework of Hofstadter`s approach we provide a detailed analysis of a
realization of exotic topological states such as the Chern insulator with large
Chern numbers. In a transverse homogeneous magnetic field a one-particle
spectrum of fermions transforms to an intricate spectrum with a fine
topological structure of the subbands. In a weak magnetic field $H$ for a
rational magnetic flux, a topological phase with a large Chern number is
realized near the half filling. There is an abnormal behavior of the Hall
conductance ${\sigma_{xy}\simeq \frac{e}{2 H}}$. At half-filling, the number of
chiral Majorana fermion edge states increases sharply forming a new state,
called the chiral Majorana fermion liquid.


title:
An extreme paucity of second population AGB stars in the normal globular
  cluster M4

abstract:
  Galactic Globular clusters (GCs) are now known to harbour multiple stellar
populations, which are chemically distinct in many light element abundances. It
is becoming increasingly clear that asymptotic giant branch (AGB) stars in GCs
show different abundance distributions in light elements compared to those in
the red giant branch (RGB) and other phases, skewing toward more primordial,
field-star-like abundances, which we refer to as subpopulation one (SP1). As
part of a larger program targeting giants in GCs, we obtained high-resolution
spectra for a sample of 106 RGB and 15 AGB stars in Messier 4 (NGC 6121) using
the 2dF+HERMES facility on the Anglo-Australian Telescope. In this Letter we
report an extreme paucity of AGB stars with [Na/O] > -0.17 in M4, which
contrasts with the RGB that has abundances up to [Na/O] =0.55. The AGB
abundance distribution is consistent with all AGB stars being from SP1. This
result appears to imply that all subpopulation two stars (SP2; Na-rich, O-poor)
avoid the AGB phase. This is an unexpected result given M4's horizontal branch
morphology -- it does not have an extended blue horizontal branch. This is the
first abundance study to be performed utilising the HERMES spectrograph.


title: Belyi's theorem for complete intersections of general type

abstract:
  We give a Belyi-type characterisation of smooth complete intersections of
general type over $\mathbb{C}$ which can be defined over $\bar{\mathbb{Q}}$.
Our proof uses the higher-dimensional analogue of the Shafarevich boundedness
conjecture for families of canonically polarized varieties, finiteness results
for maps to varieties of general type, and rigidity theorems for Lefschetz
pencils of complete intersections.


title:
Storage and retrieval of (3+1)-dimensional weak-light bullets and
  vortices in a coherent atomic gas

abstract:
  A robust light storage and retrieval (LSR) in high dimensions is highly
desirable for light and quantum information processing. However, most schemes
on LSR realized up to now encounter problems due to not only dissipation, but
also dispersion and diffraction, which make LSR with a very low fidelity. Here
we propose a scheme to achieve a robust storage and retrieval of weak nonlinear
high-dimensional light pulses in a coherent atomic gas via electromagnetically
induced transparency. We show that it is available to produce stable
(3+1)-dimensional light bullets and vortices, which have very attractive
physical property and are suitable to obtain a robust LSR in high dimensions.


title:
Effectively computing integral points on the moduli of smooth quartic
  curves

abstract:
  We prove an effective version of the Shafarevich conjecture (as proven by
Faltings) for smooth quartic curves. To do so, we establish an effective
version of Scholl's finiteness result for smooth del Pezzo surfaces of degree
at most four.


title: On Modular and Fully-Abstract Compilation -- Technical Appendix

abstract:
  Secure compilation studies compilers that generate target-level components
that are as secure as their source-level counterparts. Full abstraction is the
most widely-proven property when defining a secure compiler. A compiler is
modular if it allows different components to be compiled independently and then
to be linked together to form a whole program. Unfortunately, many existing
fully-abstract compilers to untyped machine code are not modular. So, while
fully-abstractly compiled components are secure from malicious attackers, if
they are linked against each other the resulting component may become
vulnerable to attacks. This paper studies how to devise modular, fully-abstract
compilers. It first analyses the attacks arising when compiled programs are
linked together, identifying security threats that are due to linking. Then, it
defines a compiler from an object-based language with method calls and dynamic
memory allocation to untyped assembly language extended with a memory isolation
mechanism. The paper provides a proof sketch that the defined compiler is
fully-abstract and modular, so its output can be linked together without
introducing security violations.


title: LHCb VELO Upgrade

abstract:
  The upgrade of the LHCb experiment, scheduled for LHC Run-III, scheduled to
start in 2021, will transform the experiment to a trigger-less system reading
out the full detector at 40 MHz event rate. All data reduction algorithms will
be executed in a high-level software farm enabling the detector to run at
luminosities of $2\times10^{33} \mathrm{cm}^{-2}\mathrm{s}^{-1}$.
  The Vertex Locator (VELO) is the silicon vertex detector surrounding the
interaction region. The current detector will be replaced with a hybrid pixel
system equipped with electronics capable of reading out at 40 MHz. The upgraded
VELO will provide fast pattern recognition and track reconstruction to the
software trigger. The silicon pixel sensors have $55\times55 \mu m^{2}$ pitch,
and are read out by the VeloPix ASIC, from the Timepix/Medipix family. The
hottest region will have pixel hit rates of 900 Mhits/s yielding a total data
rate of more than 3 Tbit/s for the upgraded VELO. The detector modules are
located in a separate vacuum, separated from the beam vacuum by a thin custom
made foil. The foil will be manufactured through milling and possibly thinned
further by chemical etching.
  The material budget will be minimised by the use of evaporative CO$_2$
coolant circulating in microchannels within 400 $\mu m$ thick silicon
substrates. The current status of the VELO upgrade is described and latest
results from operation of irradiated sensor assemblies are presented.


title:
Trapping of Weak Signal Pulses by Soliton and Trajectory Control in a
  Coherent Atomic Gas

abstract:
  We propose a method for trapping weak signal pulses by soliton and realizing
its trajectory control via electromagnetically induced transparency (EIT). The
system we consider is a cold, coherent atomic gas with a tripod or multipod
level configuration. We show that, due to the giant enhancement of Kerr
nonlinearity contributed by EIT, several weak signal pulses can be effectively
trapped by a soliton and cotravel stably with ultraslow propagating velocity.
Furthermore, we demonstrate that the trajectories of the soliton and the
trapped signal pulses can be manipulated by using a Stern-Gerlach gradient
magnetic field. As a result, the soliton and the trapped signal pulses display
a Stern-Gerlach deflection and both of them can bypass an obstacle together.
The results predicted here may be used to design all-optical switching at very
low light level.


title: From Dynamic to Static Semantics, Quantitatively

abstract:
  We exhibit a new relationship between dynamic and static semantics. We define
the categorical outlay needed to define Interaction Graphs models, a
generalisation of Girard's Geometry of Interaction models, which strongly
relate to game semantics. We then show how this category is mapped to weighted
relational models of linear logic. This brings into vision a new bridge between
the dynamic and static approaches, and provides formal grounds for considering
interaction graphs models as quantitative versions of GoI and game semantics
models. We finally proceed to show how the interaction graphs models relate to
a very general notion of quantitative coherence spaces.


title:
Balancing Data Security and Blocking Performance with Spectrum
  Randomization in Optical Networks

abstract:
  Data randomization or scrambling has been effectively used in various
applications to improve the data security. In this paper, we use the idea of
data randomization to proactively randomize the spectrum (re)allocation to
improve connections' security. As it is well-known that random (re)allocation
fragments the spectrum and thus increases blocking in elastic optical networks,
we analyze the tradeoff between system performance and security. To this end,
in addition to spectrum randomization, we utilize an on-demand defragmentation
scheme every time a request is blocked due to the spectrum fragmentation. We
model the occupancy pattern of an elastic optical link (EOL) using a
multi-class continuous-time Markov chain (CTMC) under the random-fit spectrum
allocation method. Numerical results show that although both the blocking and
security can be improved for a particular so-called randomization process (RP)
arrival rate, while with the increase in RP arrival rate the connections'
security improves at the cost of the increase in overall blocking.


title:
Stern-Gerlach effect of multi-component ultraslow optical solitons via
  electromagnetically induced transparency

abstract:
  We propose a scheme to exhibit a Stern-Gerlach effect of n-component (n > 2)
high-dimensional ultraslow optical solitons in a coherent atomic system with (n
+ 1)-pod level configuration via electromagnetically induced transparency
(EIT). Based on Maxwell-Bloch equations, we derive coupled (3+1)-dimensional
nonlinear Schrodinger equations governing the spatial-temporal evolution of n
probe-field envelopes. We show that under EIT condition significant deflections
of the n components of coupled ultraslow optical solitons can be achieved by
using a Stern-Gerlach gradient magnetic field. The stability of the ultraslow
optical solitons can be realized by an optical lattice potential contributed
from a far-detuned laser field.


title:
The disappearance of the helium-giant progenitor of the type Ib
  supernova iPTF13bvn and constraints on its companion

abstract:
  We report and discuss post-explosion observations of supernova iPTF13bvn. We
find that the brightness of the SN at +740 days is below the level of the
pre-explosion source and thus confirm that the progenitor star has gone. We
estimate that the late-time brightness is still dominated by the supernova,
which constrains the magnitude and thus mass of a possible companion star to
below approximately 10Msun. In turn this implies that the progenitor's initial
mass is constrained to a narrow range of between 10 to 12Msun. The progenitor
of iPTF13bvn would have been a helium giant rather than a Wolf-Rayet star. In
addition, we suggest that sufficiently deep observations acquired in 2016 would
now stand a chance to directly observe the companion star.


title:
Scattering and bound states of a spin--1/2 neutral particle in the
  cosmic string spacetime

abstract:
  In this paper the relativistic quantum dynamics of a spin-1/2 neutral
particle with a magnetic moment $\mu$ in the cosmic string spacetime is
reexamined by applying the von Neumann theory of self--adjoint extensions.
Contrary to previous studies where the interaction between the spin and the
line of charge is neglected, here we consider its effects. This interaction
gives rise to a point interaction: $\boldsymbol{\nabla} \cdot \mathbf{E}=
(2\lambda/\alpha)\delta(r)/r$. Due to the presence of the Dirac delta function,
by applying an appropriated boundary condition provided by the theory of
self--adjoint extensions, irregular solutions for the Hamiltonian are allowed.
We address the scattering problem obtaining the phase shift, S-matrix and the
scattering amplitude. The scattering amplitude obtained shows a dependency with
energy which stems from the fact that the helicity is not conserved in this
system. Examining the poles of the S-matrix we obtain an expression for the
bound states. The presence of bound states for this system has not been
discussed before in the literature.


title: Universality of the Einstein theory of gravitation

abstract:
  We show that generalizations of general relativity theory, which consist in
replacing the Hilbert Lagrangian $L_{Hilbert} = \frac 1{16\pi} \sqrt{|g|} R$ by
a generic scalar density $L=L(g_{\mu\nu}, R^\lambda_{\mu\nu\kappa})$ depending
upon the metric $g_{\mu\nu}$ and the curvature tensor
$R^\lambda_{\mu\nu\kappa}$, are equivalent to the conventional Einstein theory
for a (possibly) different metric tensor $\tilde{g}_{\mu\nu}$ and (possibly) a
different set of matter fields. The simple proof of this theorem relies on a
new approach to variational problems containing metric and connection.


title:
Frequency-Domain Response Based Timing Synchronization: A Near Optimal
  Sampling Phase Criterion for TDS-OFDM

abstract:
  In time-domain synchronous OFDM (TDS-OFDM) system for digital television
terrestrial multimedia broadcasting (DTMB) standard, the baseband OFDM signal
is upsampled and shaping filtered by square root raised cosine (SRRC) filter
before digital-to-analog converter (DAC). Much of the work in the area of
timing synchronization for TDS-OFDM focuses on frame synchronization and
sampling clock frequency offset recovery, which does not consider the sampling
clock phase offset due to the upsampling and SRRC filter. This paper evaluates
the bit-error-rate (BER) effect of sampling clock phase offset in TDS-OFDM
system. First, we provide the BER for M-order quadrature amplitude modulation
(M-QAM) in uncoded TDS-OFDM system. Second, under the condition of the optimal
BER criterion and additive white Gaussian noise (AWGN) channel, we propose a
near optimal sampling phase estimation criterion based on frequency-domain
response. Simulations demonstrate that the proposed criterion also has good
performance in actual TDS-OFDM system with channel coding over multipath
channels, and it is superior to the conventional symbol timing recovery methods
for TDS-OFDM system.


title:
A matrix-algebraic algorithm for the Riemannian logarithm on the Stiefel
  manifold under the canonical metric

abstract:
  We derive a numerical algorithm for evaluating the Riemannian logarithm on
the Stiefel manifold with respect to the canonical metric. In contrast to the
existing optimization-based approach, we work from a purely matrix-algebraic
perspective. Moreover, we prove that the algorithm converges locally and
exhibits a linear rate of convergence.


title:
QoS Constrained Power Minimization in the Multiple Stream MIMO Broadcast
  Channel

abstract:
  This work addresses the design of optimal linear transmit filters for the
Multiple Input-Multiple Output (MIMO) Broadcast Channel (BC) when several
spatial streams are allocated to each user.We also consider that the Channel
State Information (CSI) is perfect at the receivers but is only partial at the
transmitter. A statistical model for the partial CSI is assumed and exploited
for the filter design. Similarly to the single-stream per user case, the
problem is solved via Mean Square Error (MSE) dualities and interference
functions. However, including more streams per user involves an additional
complexity level since we must determine how to distribute the per-user rates
among the streams. Such problem is solved using a projected gradient algorithm.


title:
A multiscale approach to the migration of cancer stem cells:
  mathematical modelling and simulations

abstract:
  We propose a multiscale model of the invasion of the extracellular matrix by
two types of cancer cells, the differentiated cancer cells and the cancer stem
cells. We assume that the epithelial mesenchymal-like transition between them
is driven primarily by the epidermal growth factors. We moreover take into
account the transidifferentiation program of the cancer stem cells and the
cancer associated fibroblast cells as well as the fibroblast-driven remodelling
of the extracellular matrix.
  The proposed haptotaxis model combines the macroscopic phenomenon of the
invasion of the extracellular matrix with the microscopic dynamics of the
epidermal growth factors. We analyse our model in a component-wise manner and
compare our findings with the literature. We investigate pathological
situations regarding the epidermal growth factors and accordingly propose
"mathematical-treatment" scenarios to control the aggressiveness of the tumour.


title: A characterization of the ball

abstract:
  We study bounded domains with certain smoothness conditions and the
properties of their squeezing functions in order to prove that the domains are
biholomorphic to the ball.


title: Optical Onion Routing

abstract:
  As more and more data is transmitted in the configurable optical layer,
whereby all optical switches forward packets without electronic layers
involved, we envision privacy as the intrinsic property of future optical
networks. In this paper, we propose Optical Onion Routing (OOR) routing and
forwarding techniques, inspired by the onion routing in the Internet layer, the
best known realization of anonymous communication today, but designed with
specific features innate to optical networks. We propose to design the optical
anonymization network system with a new optical anonymization node
architecture, including the optical components and their electronic
counterparts to realize layered encryption. We propose modification to the
secret key generation using Linear Feedback Shift Register (LFSR), able to
utilize different primitive irreducible polynomials, and the usage optical XOR
operation as encryption, an important optical technology coming of age. We
prove formally that, for the proposed encryption techniques and distribution of
secret information, the optical onion network is perfectly private and secure.
The paper aims at providing practical foundations for privacy-enhancing optical
network technologies.


title:
The High Temperature Superconductivity in Cuprates: Physics of the
  Pseudogap Region

abstract:
  We discuss the physics of the high temperature superconductivity in hole
doped copper oxide ceramics in the pseudogap region. Starting from an effective
reduced Hamiltonian relevant to the dynamics of holes injected into the copper
oxide layers proposed in a previous paper, we determine the superconductive
condensate wavefunction. We show that the low-lying elementary condensate
excitations are analogous to the rotons in superfluid $^4He$. We argue that the
rotons-like excitations account for the specific heat anomaly at the critical
temperature. We discuss and compare with experimental observations the London
penetration length, the Abrikosov vortices, the upper and lower critical
magnetic fields, and the critical current density. We give arguments to explain
the origin of the Fermi arcs and Fermi pockets. We investigate the nodal gap in
the cuprate superconductors and discuss both the doping and temperature
dependence of the nodal gap. We suggest that the nodal gap is responsible for
the doping dependence of the so-called nodal Fermi velocity detected in angle
resolved photoemission spectroscopy studies. We discuss the thermodynamics of
the nodal quasielectron liquid and their role in the low temperature specific
heat. We propose that the ubiquitous presence of charge density wave in hole
doped cuprate superconductors in the pseudogap region originates from
instabilities of the nodal quasielectrons driven by the interaction with the
planar $CuO_2$ lattice. We investigate the doping dependence of the charge
density wave gap and the competition between charge order and
superconductivity. We discuss the effects of external magnetic fields on the
charge density wave gap and elucidate the interplay between charge density wave
and Abrikosov vortices. Finally, we examine the physics underlying quantum
oscillations in the pseudogap region.


title: Lagrangian submanifolds in the nearly kaehler $s^3 \times s^3$

abstract:
  In this paper, we investigate Lagrangian submanifolds in the nearly Kaehler
$S^3 \times S^3$. We construct a new example which is a at Lagrangian torus. We
give a complete classification of all the Lagrangian immersions of spaces of
constant sectional curvature in the nearly Kaehler $S^3\times S^3$.


title:
Examples of computational approaches to accommodate randomness in
  elliptic PDEs

abstract:
  We overview a series of recent works addressing numerical simulations of
partial differential equations in the presence of some elements of randomness.
The specific equations manipulated are linear elliptic, and arise in the
context of multiscale problems, but the purpose is more general. On a set of
prototypical situations, we investigate two critical issues present in many
settings: variance reduction techniques to obtain sufficiently accurate results
at a limited computational cost when solving PDEs with random coefficients, and
finite element techniques that are sufficiently flexible to carry over to
geometries with random fluctuations. Some elements of theoretical analysis and
numerical analysis are briefly mentioned. Numerical experiments, although
simple, provide convincing evidence of the efficiency of the approaches.


title: Fragile-to-strong transition in liquid silica

abstract:
  We investigate anomalies in liquid silica with molecular dynamics simulations
and present evidence for a fragile-to-strong transition at around 3100 K-3300
K. To this purpose, we studied the structure and dynamical properties of silica
over a wide temperature range, finding four indicators of a fragile-to-strong
transition. First, there is a density minimum at around 3000 K and a density
maximum at 4700 K. The turning point is at 3400 K. Second, the local structure
characterized by the tetrahedral order parameter changes dramatically around
3000 K from a higher-ordered, lower-density phase to a less ordered,
higher-density phase. Third, the correlation time {\tau} changes from an
Arrhenius behavior below 3300 K to a Vogel-Fulcher-Tammann behavior at higher
temperatures. Fourth, the Stokes-Einstein relation holds for temperatures below
3000 K, but is replaced by a fractional relation above this temperature.
Furthermore, our data indicate that dynamics become again simple above 5000 K,
with Arrhenius behavior and a classical Stokes-Einstein relation.


title: Searching for microscopic classical cats

abstract:
  With the exception of superselection rules, there are no known explicit
violations of the Principle of quantum Superposition. However, quantum
measurement and the emergence of classicality seem to imply that the Principle
of Superposition is not universal, so perhaps new superselection rules or
something similar wait to be found. This invites us to search for explicit
violations of superposition, even in places where we expect it to hold. Given
that many quantum measurement devices rely on atoms absorbing photons, these
processes are natural places for a first search for such violations.
  We propose experiments designed to test whether the emission and absorption
of photons by atoms may suppress the interference in certain conditions. If the
atom is found, in certain situations, to absorb completely the photon, this
would mean that in those situations the atom cannot exist or at least it cannot
be stable as a superposition of states in which it absorbed the photon and it
did not absorb it. Then we will have a new possibility to resolve the problem
of measurement, and that of the emergence of classicality. A negative result
would mean an additional confirmation of the Principle of Superposition in
these particular cases.


title: An Approximation Algorithm for a Shortest Dubins Path Problem

abstract:
  The problem of finding the shortest path for a vehicle visiting a given
sequence of target points subject to the motion constraints of the vehicle is
an important problem that arises in several monitoring and surveillance
applications involving unmanned aerial vehicles. There is currently no
algorithm that can find an optimal solution to this problem. Therefore,
heuristics that can find approximate solutions with guarantees on the quality
of the solutions are useful. The best approximation algorithm currently
available for the case when the distance between any two adjacent target points
in the sequence is at least equal to twice the minimum radius of the vehicle
has a guarantee of 3.04. This article provides a new approximation algorithm
which improves this guarantee to 2.04. The developed algorithm is also
implemented for hundreds of typical instances involving at most 30 points to
corroborate the performance of the proposed approach.


title:
Generalized Centripetal Force Law and Quantization of Motion Constrained
  on 2D Surfaces

abstract:
  For a particle moves on a 2D surface f(x)=0 embedded in 3D Euclidean space,
the geometric momentum and potential are simultaneously admissible within the
Dirac canonical quantization scheme for constrained motion. In our approach,
not the full scheme but the symmetries indicated by classical brackets
[x,H]_{D} and [p,H]_{D} in addition to the fundamental ones [x,x]_{D},
[x,p]_{D} and [p,p]_{D} are utilized, where the subscript D stands for the
Dirac bracket. The generalized centripetal force law p=[p,H]_{D} for particle
on the 2D surface play the key role, and there is no simple relationship
between the force on a point of the surface and its curvatures of the point, in
sharp contrast to the motion on a curve.