title: Cortical Brain Computer Interface for Closed-Loop Deep Brain Stimulation

abstract:
  Essential Tremor is the most common neurological movement disorder. This
progressive disease causes uncontrollable rhythmic motions -most often
affecting the patient's dominant upper extremity- that occur during volitional
movement and make it difficult for the patient to perform everyday tasks.
Medication may also become ineffective as the disorder progresses. For many
patients, deep brain stimulation (DBS) of the thalamus is an effective means of
treating this condition when medication fails. In current use, however,
clinicians set the patient's stimulator to apply stimulation at all times-
whether it is needed or not. This practice leads to excess power use, and more
rapid depletion of batteries that require surgical replacement. In the work
described here, for the first time, neural sensing of movement (using
chronically-implanted cortical electrodes) is used to enable or disable
stimulation for tremor. Therapeutic stimulation is delivered only when the
patient is actively using their effected limb, thereby reducing the total
stimulation applied, and potentially extending the lifetime of
surgically-implanted batteries. This work, which involves both implanted and
external subsystems, paves the way for the future fully-implanted closed-loop
deep brain stimulators.


title: Deep Pyramidal Residual Networks with Separated Stochastic Depth

abstract:
  On general object recognition, Deep Convolutional Neural Networks (DCNNs)
achieve high accuracy. In particular, ResNet and its improvements have broken
the lowest error rate records. In this paper, we propose a method to
successfully combine two ResNet improvements, ResDrop and PyramidNet. We
confirmed that the proposed network outperformed the conventional methods; on
CIFAR-100, the proposed network achieved an error rate of 16.18% in contrast to
PiramidNet achieving that of 18.29% and ResNeXt 17.31%.


title: Simplified description of an active medium in quantum plasmonics

abstract:
  In order to simplify the theoretical description of spasers, a gain medium is
commonly represented by a two-level system. A realistic model, however, should
have four levels. By using the Lindblad equations we develop a description of
such a system and show that depending on ratios of the Rabi frequency and the
rate of relaxation of the polarization, a four-level system may be reduced to
one of two effective two-level systems that reproduce the key properties of a
four-level system.


title: Wavelet-based methods for high-frequency lead-lag analysis

abstract:
  We propose a novel framework to investigate lead-lag relationships between
two financial assets. Our framework bridges a gap between continuous-time
modeling based on Brownian motion and the existing wavelet methods for lead-lag
analysis based on discrete-time models and enables us to analyze the
multi-scale structure of lead-lag effects. We also present a statistical
methodology for the scale-by-scale analysis of lead-lag effects in the proposed
framework and develop an asymptotic theory applicable to a situation including
stochastic volatilities and irregular sampling. Finally, we report several
numerical experiments to demonstrate how our framework works in practice.


title:
Phosphorylation potential and chemical fluxes govern the biological
  performance of multiple PdP cycles

abstract:
  Fission yeast G2/M transition is regulated by a biochemical reaction networks
which contains four components: Cdc13, Cdc2, Wee1, and Cdc25. This circuit is
characterized by the ultrasensitive responses of Wee1 or Cdc25 to Cdc13/Cdc2
activity, and the bistability of Cdc2 activation. Previous work has shown that
this bistability is governed by phosphorylation energy. In this article, we
developed the kinetic model of this circuit and conducted further thermodynamic
analysis on the role of phosphorylation energy (&[Delta]G). We showed that
level &[Delta]G shapes the response curves of Wee1 or Cdc25 to Cdc2 and governs
the intrinsic noise level of Cdc2 activity. More importantly, the mutually
antagonistic chemical fluxes around the PdP cycles in G2/M circuit were shown
to act as a stabilizer of Cdc2 activity against &[Delta]G fluctuations. These
results suggests the fundamental role of free energy and chemical fluxes on the
sensitivity, bistability and robustness of G2/M transition.


title: Multi-way Particle Swarm Fusion

abstract:
  This paper proposes a novel MAP inference framework for Markov Random Field
(MRF) in parallel computing environments. The inference framework, dubbed Swarm
Fusion, is a natural generalization of the Fusion Move method. Every thread (in
a case of multi-threading environments) maintains and updates a solution. At
each iteration, a thread can generate arbitrary number of solution proposals
and take arbitrary number of concurrent solutions from the other threads to
perform multi-way fusion in updating its solution. The framework is general,
making popular existing inference techniques such as alpha-expansion, fusion
move, parallel alpha-expansion, and hierarchical fusion, its special cases. We
have evaluated the effectiveness of our approach against competing methods on
three problems of varying difficulties, in particular, the stereo, the optical
flow, and the layered depthmap estimation problems.


title: Turning an Urban Scene Video into a Cinemagraph

abstract:
  This paper proposes an algorithm that turns a regular video capturing urban
scenes into a high-quality endless animation, known as a Cinemagraph. The
creation of a Cinemagraph usually requires a static camera in a carefully
configured scene. The task becomes challenging for a regular video with a
moving camera and objects. Our approach first warps an input video into the
viewpoint of a reference camera. Based on the warped video, we propose
effective temporal analysis algorithms to detect regions with static geometry
and dynamic appearance, where geometric modeling is reliable and visually
attractive animations can be created. Lastly, the algorithm applies a sequence
of video processing techniques to produce a Cinemagraph movie. We have tested
the proposed approach on numerous challenging real scenes. To our knowledge,
this work is the first to automatically generate Cinemagraph animations from
regular movies in the wild.


title: Loop Quantum Cosmology: A brief review

abstract:
  In the last decade, progress on quantization of homogeneous cosmological
spacetimes using techniques of loop quantum gravity has led to insights on
various fundamental questions and has opened new avenues to explore Planck
scale physics. These include the problem of singularities and their possible
generic resolution, constructing viable non-singular models of the very early
universe, and bridging quantum gravity with cosmological observations. These
results, which emerge from an interplay of sophisticated analytical and
numerical techniques, has also led to valuable hints on loop quantization of
black hole and inhomogeneous spacetimes. In this review, we provide a summary
of this progress while focusing on concrete examples of the quantization
procedure and phenomenology of cosmological perturbations.


title:
Cancerous Nuclei Detection and Scoring in Breast Cancer
  Histopathological Images

abstract:
  Early detection and prognosis of breast cancer are feasible by utilizing
histopathological grading of biopsy specimens. This research is focused on
detection and grading of nuclear pleomorphism in histopathological images of
breast cancer. The proposed method consists of three internal steps. First,
unmixing colors of H&E is used in the preprocessing step. Second, nuclei
boundaries are extracted incorporating the center of cancerous nuclei which are
detected by applying morphological operations and Difference of Gaussian filter
on the preprocessed image. Finally, segmented nuclei are scored to accomplish
one parameter of the Nottingham grading system for breast cancer. In this
approach, the nuclei area, chromatin density, contour regularity, and nucleoli
presence, are features for nuclear pleomorphism scoring. Experimental results
showed that the proposed algorithm, with an accuracy of 86.6%, made significant
advancement in detecting cancerous nuclei compared to existing methods in the
related literature.


title: The BRAN luminosity detectors for the LHC

abstract:
  This paper describes the several phases which led, from the conceptual
design, prototyping, construction and tests with beam, to the installation and
operation of the BRAN (Beam RAte of Neutrals) relative luminosity monitors for
the LHC. The detectors have been operating since 2009 to contribute, optimize
and maintain the accelerator performance in the two high luminosity interaction
regions (IR), the IR1 (ATLAS) and the IR5 (CMS). The devices are gas ionization
chambers installed inside a neutral particle absorber 140 m away from the
Interaction Points in IR1 and IR5 and monitor the energy deposited by
electromagnetic showers produced by high-energy neutral particles from the
collisions. The detectors have the capability to resolve the bunch-by-bunch
luminosity at the 40 MHz bunch rate, as well as to survive the extreme level of
radiation during the nominal LHC operation. The devices have operated since the
early commissioning phase of the accelerator over a broad range of luminosities
reaching 1.4*10^34 cm-2 s-1 with a peak pileup of 45 events per bunch crossing.
Even though the nominal design luminosity of the LHC has been exceeded, the
BRAN is operating well. After describing the multiple applications that the
BRAN can be used to monitor the luminosity of the accelerator, we discuss the
technical choices that led to its construction and the different tests
performed prior to the installation in two IRs of the LHC. Performance
simulations are presented together with operational results obtained during p-p
operations, including runs at 40 MHz bunch rate, Pb-Pb operations and p-Pb
operations.


title: Sub-picosecond acoustic pulses at buried GaP/Si interfaces

abstract:
  We report on the optical generation and detection of ultrashort acoustic
pulses that propagate in three-dimensional semiconductor crystals.
Photoexcitaiton of lattice-matched GaP layers grown on Si(001) gives rise to a
sharp spike in transient reflectivity due to the acoustic pulse generated at
the GaP/Si interface and detected at the GaP surface and vice versa. The
extremely short width of the reflectivity spike, 0.5 ps, would translate to a
spatial extent of 3 nm or 10 atomic bilayers, which is comparable with the
width of the intermixing layer at the GaP/Si interface. The reflectivity
signals are also modified by quasi-periodic Brillouin oscillations of GaP and
Si arising from the acoustic pulses during the propagation in the crystals. The
present results demonstrate the potential application of the simple optical
pump-probe scheme in the nondestructive evaluation of the buried semiconductor
interface quality.


title:
{\pi}-Conjugation in Epitaxial Si(111)-($\sqrt3$$\times$$\sqrt3$)
  Surface: an Unconventional "Bamboo Hat" Bonding Geometry for Si

abstract:
  The newly observed ($\sqrt3$$\times$$\sqrt3$) surface reconstruction in
heteroepitaxial Si(111) thin films on metal substrates is widely considered as
a promising platform to realize 2D Dirac and topological states, yet its
formation mechanism and structural stability are poorly understood, leading to
the controversial terminology of "multilayer silicene". Based on valence bond
and conjugation theory, we propose a {\pi}-conjugation plus charge-transfer
model to elucidate such a unique "bamboo hat" surface geometry. The formation
of planar ring-shaped {\pi}-conjugation and charge transfer from the rings to
upper buckled Si atoms greatly lower the surface dangling bond energy. We
justify this unconventional Si structural model by analyzing from
first-principles surface energies and surface stress tensors as a function of
strain. Within the same formalism, additional metastable surface
reconstructions with the similar "bamboo hat" features are predicted which
opens possibilities to other exotic electronic states in silicon.


title: An electric-resistance approach to return time

abstract:
  A new proof is given for the formula for the expected return time of a random
walk on a graph. This proof makes use of known relationships between electric
resistance and random walks.


title:
Full rank presentations and nilpotent groups: structure, Diophantine
  problem, and genericity

abstract:
  We study finitely generated nilpotent groups $G$ given by full rank finite
presentations $\langle A \mid R\rangle$ in the variety $\mathcal{N}_c$ of
nilpotent groups of class at most $c$, where $c \geq 2$. We prove that if the
deficiency $|A| - |R| $ is at least $2$ then the group $G$ is virtually free
nilpotent, it is quasi finitely axiomatizable (in particular, first-order
rigid), and it is almost (up to finite factors) directly indecomposable. One of
the main results of the paper is that the Diophantine problem in nilpotent
groups given by full rank finite presentations $\langle A \mid R\rangle$ is
undecidable if $|A| - |R| \geq 2$ and decidable otherwise. We show that this
class of groups is rather large since finite presentations asymptotically
almost surely have full rank, so a random nilpotent group in the few relators
model has a full rank presentation asymptotically almost surely. Full rank
presentations give one a useful tool to approach random nilpotent groups and
study their properties. Note, that the results above significantly improve our
understanding of the Diophantine problem in finitely generated nilpotent
groups: from a few special examples of groups with undecidable Diophantine
problem we got to the place where we know that the Diophantine problem in all
"typical" nilpotent groups is also undecidable.


title:
Vehicle Powertrain Connected Route Optimization for Conventional, Hybrid
  and Plug-in Electric Vehicles

abstract:
  Most navigation systems use data from satellites to provide drivers with the
shortest-distance, shortest-time or highway-preferred paths. However, when the
routing decisions are made for advanced vehicles, there are other factors
affecting cost, such as vehicle powertrain type, battery state of charge (SOC)
and the change of component efficiencies under traffic conditions, which are
not considered by traditional routing systems. The impact of the trade-off
between distance and traffic on the cost of the trip might change with the type
of vehicle technology and component dynamics. As a result, the least-cost paths
might be different from the shortest-distance or shortest-time paths. In this
work, a novel routing strategy has been proposed where the decision-making
process benefits from the aforementioned information to result in a least-cost
path for drivers. We integrate vehicle powertrain dynamics into route
optimization and call this strategy as Vehicle Powertrain Connected Route
Optimization (VPCRO). We find that the optimal paths might change significantly
for all types of vehicle powertrains when VPCRO is used instead of
shortest-distance strategy. About 81% and 58% of trips were replaced by
different optimal paths with VPCRO when the vehicle type was Conventional
Vehicle (CV) and Electrified Vehicle (EV), respectively. Changed routes had
reduced travel costs on an average of 15% up to a maximum of 60% for CVs and on
an average of 6% up to a maximum of 30% for EVs. Moreover, it was observed that
3% and 10% of trips had different optimal paths for a plug-in hybrid electric
vehicle, when initial battery SOC changed from 90% to 60% and 40%,
respectively. Paper shows that using sensory information from vehicle
powertrain for route optimization plays an important role to minimize travel
costs.


title:
Antiholomorphic perturbations of Weierstrass Zeta functions and Green's
  function on tori

abstract:
  In \cite{BeEr}, Bergweiler and Eremenko computed the number of critical
points of the Green's function on a torus by investigating the dynamics of a
certain family of antiholomorphic meromorphic functions on tori. They also
observed that hyperbolic maps are dense in this family of meromorphic functions
in a rather trivial way. In this paper, we study the parameter space of this
family of meromorphic functions, which can be written as antiholomorphic
perturbations of Weierstrass Zeta functions. On the one hand, we give a
complete topological description of the hyperbolic components and their
boundaries, and on the other hand, we show that these sets admit natural
parametrizations by associated dynamical invariants. This settles a conjecture,
made in \cite{LW}, on the topology of the regions in the upper half plane
$\mathbb{H}$ where the number of critical points of the Green's function
remains constant.


title:
An Information-Theoretic Approach to Optimize JWST Observations and
  Retrievals of Transiting Exoplanet Atmospheres

abstract:
  We provide an example of an analysis to explore the optimization of
observations of transiting hot jupiters with JWST to characterize their
atmospheres, based on a simple three-parameter forward model. We construct
expansive forward model sets for eleven hot jupiters, ten of which are
relatively well-characterized, exploring a range of parameters such as
equilibrium temperature and metallicity, as well as considering host stars over
a wide range in brightness. We compute posterior distributions of our model
parameters for each planet with all of the available JWST spectroscopic modes
and several programs of combined observations and compute their effectiveness
using the metric of estimated mutual information per degree of freedom. From
these simulations, clear trends emerge that provide guidelines for designing a
JWST observing program. We demonstrate that these guidelines apply over a wide
range of planet parameters and target brightnesses for our simple forward
model.


title: Voltage Control in the Presence of Photovoltaic Systems

abstract:
  In the past decade, the landscape of energy production has had to shift to
accommodate renewables. Which, unlike fossil fuels, are subject to frequent
fluctuations; potentially destabilizing grid operators. With the continued
demand for solar PV system installation, there is a pressing need for utilities
to regulate the voltages at the low voltage distribution grids. We develop a
stochastic model for voltage rise as a function of injected power into the
grid. This model is formed as a linear combination of gamma random variables.
This is achieved by finding sparse bases and clustering the data into subsets
by its correlation with those bases, and fitting a gamma distribution within
each subset. We are concerned with modeling voltage rise, while taking into
account sparse events in the voltage. We use sparse singular value
decomposition (SVD) with $\ell_1$ penalty to model sparse voltage rise. More
randomness and disorder in voltage rises was observed at the point of common
coupling (PCC) of the PV systems with greater line impedance. A controller to
regulate the voltage at the PCC of a single phase solar PV system is presented.
This controller uses the stochastic model to minimize the risk of voltage rise.
Simulation results confirm that this voltage controller can lower the voltage
more effectively than conventional voltage regulators during periods of high
solar PV output.


title:
Charged Lifshitz black hole and probed Lorentz-violation fermions from
  holography

abstract:
  We analytically obtain a new charged Lifshtitz solution by adding a
non-relativistic Maxwell field in Horava-Lifshitz gravity. The black hole
exhibits an anisotropic scaling between space and time (Lifshitz scaling) in
the UV limit, while in the IR limit, the Lorentz invariance is recovered. We
introduce the probed Lorentz-violation fermions into the background and
holographically investigate the spectral properties of the dual fermionic
operator. The Lorentz-violation of fermions will enhance the peak and
corresponds larger fermi momentum, which compensates the non-relativistic bulk
effect of the dynamical exponent. For a fixed $z$, when the Lorentz-violation
of fermions increases to a critical value, the behavior of the low energy
excitation goes from a non-Fermi liquid type to a fermi liquid type, which
implies a kind of phase transition.


title:
Perturbative dissipation dynamics of a weakly driven Jaynes-Cummings
  system

abstract:
  We generalize a microscopic master equation method to study the dissipation
dynamics of Jaynes-Cummings two-level system with a weak external driving.
Using perturbative analysis to extend the damping bases theory, we derive the
corrected Rabi oscillation and vaccum Rabi splitting analytically. The
evolution of the decoherence factor of the weakly driven system reveals that
the off-diagonal density matrix elements are oscillating at a frequency
dependent on the driving strength and the initial population inversion. For
highly-inverted systems at the weak-driving limit, this frequency reduces to
twice the value for the non-driven system, showing the dissipation dynamics
unable to be discovered using more conventional approaches.


title:
Static Non-Linearity Based Analysis of Non-Resonant MOSFET as THz
  Detector

abstract:
  The non-resonant THz response of CMOS FET has been analyzed based on static
non-linearities of the transistor channel. Under the quasi-static limit, the
second order non-linearities dominantly determine the DC current in the channel
generated in response to THz signal. For the applied gate-to source and
drain-to-source signals, the significance of the second order non-linear terms
is analyzed as a function of DC bias conditions. Based on the analysis, it has
also been shown that a differential detector topology can give highest
responsivity in cold operation. A tradeoff between the channel resistance and
load impedance plays a vital role in detecting the generated current. Moreover,
the design considerations such as readout modes, optimum bias points and device
dimensions are also discussed with respect to both responsivity and noise
equivalent power (NEP).


title:
Model-Stable Universality of the Air Shower Electromagnetic Component:
  an Approach to Solving the Mass Composition Problem

abstract:
  On the basis of the scaling approach and CORSIKA simulations data the radial
scale factor of lateral distribution of electrons in extensive air showers is
confirmed as potentially effective primary mass estimator, and its sensitivity
to hadronic interaction model is investigated. It is shown that improved
composition results both on average and event-by-event basis can be achieved
taking into account the universality property of air shower development
expressed by the relation between radial scale factor and longitudinal age
parameter. The enhancements of such a theoretically motivated tool for the
unbiased cosmic ray composition deduction in a wide primary energy range from
(multi-)hybrid air shower measurements of nearest future are discussed.


title: Known Unknowns: Uncertainty Quality in Bayesian Neural Networks

abstract:
  We evaluate the uncertainty quality in neural networks using anomaly
detection. We extract uncertainty measures (e.g. entropy) from the predictions
of candidate models, use those measures as features for an anomaly detector,
and gauge how well the detector differentiates known from unknown classes. We
assign higher uncertainty quality to candidate models that lead to better
detectors. We also propose a novel method for sampling a variational
approximation of a Bayesian neural network, called One-Sample Bayesian
Approximation (OSBA). We experiment on two datasets, MNIST and CIFAR10. We
compare the following candidate neural network models: Maximum Likelihood,
Bayesian Dropout, OSBA, and --- for MNIST --- the standard variational
approximation. We show that Bayesian Dropout and OSBA provide better
uncertainty information than Maximum Likelihood, and are essentially equivalent
to the standard variational approximation, but much faster.


title:
Suppression of Stimulated Raman Scattering and Hot Electrons Generation
  due to Langmuir Decay Instability Cascade and Langmuir Collapse

abstract:
  Backward stimulated Raman scattering (BSRS) with Langmuir decay instability
(LDI) and Langmuir collapse has been researched by Vlasov simulation for the
first time. The decay productions of LDI cascade and their evolution with time
is clearly demonstrated, which occurs simultaneously with Langmuir collapse.
The BSRS reflectivity will be decreased largely through LDI cascade and
Langmuir collapse. In CH plasmas, when $T_i/T_e=1/3$, the Landau damping of the
slow ion-acoustic wave (IAW) is lower than that in H plasmas. Therefore, the
BSRS can be further suppressed through LDI cascade by the way of controlling
the species of plasmas and ions ratio. These results give an effective
mechanism to suppress the BSRS and hot electrons generation.


title: Deep Image Category Discovery using a Transferred Similarity Function

abstract:
  Automatically discovering image categories in unlabeled natural images is one
of the important goals of unsupervised learning. However, the task is
challenging and even human beings define visual categories based on a large
amount of prior knowledge. In this paper, we similarly utilize prior knowledge
to facilitate the discovery of image categories. We present a novel end-to-end
network to map unlabeled images to categories as a clustering network. We
propose that this network can be learned with contrastive loss which is only
based on weak binary pair-wise constraints. Such binary constraints can be
learned from datasets in other domains as transferred similarity functions,
which mimic a simple knowledge transfer. We first evaluate our experiments on
the MNIST dataset as a proof of concept, based on predicted similarities
trained on Omniglot, showing a 99\% accuracy which significantly outperforms
clustering based approaches. Then we evaluate the discovery performance on
Cifar-10, STL-10, and ImageNet, which achieves both state-of-the-art accuracy
and shows it can be scalable to various large natural images.


title:
Deep Symbolic Representation Learning for Heterogeneous Time-series
  Classification

abstract:
  In this paper, we consider the problem of event classification with
multi-variate time series data consisting of heterogeneous (continuous and
categorical) variables. The complex temporal dependencies between the variables
combined with sparsity of the data makes the event classification problem
particularly challenging. Most state-of-art approaches address this either by
designing hand-engineered features or breaking up the problem over homogeneous
variates. In this work, we propose and compare three representation learning
algorithms over symbolized sequences which enables classification of
heterogeneous time-series data using a deep architecture. The proposed
representations are trained jointly along with the rest of the network
architecture in an end-to-end fashion that makes the learned features
discriminative for the given task. Experiments on three real-world datasets
demonstrate the effectiveness of the proposed approaches.


title:
The First Eigenvalue for the Bi-Beltrami-Laplacian on Minimal
  Isoparametric Hypersurfaces of $\mathbb{S}^{n+1}(1)$

abstract:
  In this paper, we investigate the first eigenvalues of two closed eigenvalue
problems of the bi-Beltrami-Laplacian on minimal embedded isoparametric
hypersurface in the unit sphere $\mathbb{S}^{n+1}(1)$. Although many
mathematicians want to derive the corresponding results for the first
eigenvalues of bi-Beltrami-Laplacian, they encountered great difficulties in
proving the limit theorem of the version of bi-Beltrami-Laplacian along with
the strategy due to I. Chavel and E. A. Feldman(Journal of Functional Analysis,
30 (1978), 198-222) and S. Ozawa (Duke Mathematics Journal, 48 (1981),767-778).
Therefore, as the author knows, there are no any results of Tang-Yan type(
Journal of Differential Geometry, 94 (2013) 521-540). However, by the
variational argument, we overcome the difficulties and determine the first
eigenvalues of the bi-Beltrami-Laplacian in the sense of isoparametric
hypersurfaces. We note that our proof is quite simple.


title: Panoramic Structure from Motion via Geometric Relationship Detection

abstract:
  This paper addresses the problem of Structure from Motion (SfM) for indoor
panoramic image streams, extremely challenging even for the state-of-the-art
due to the lack of textures and minimal parallax. The key idea is the fusion of
single-view and multi-view reconstruction techniques via geometric relationship
detection (e.g., detecting 2D lines as coplanar in 3D). Rough geometry suffices
to perform such detection, and our approach utilizes rough surface normal
estimates from an image-to-normal deep network to discover geometric
relationships among lines. The detected relationships provide exact geometric
constraints in our line-based linear SfM formulation. A constrained linear
least squares is used to reconstruct a 3D model and camera motions, followed by
the bundle adjustment. We have validated our algorithm on challenging datasets,
outperforming various state-of-the-art reconstruction techniques.


title: Height estimates for Killing graphs

abstract:
  The paper aims at proving global height estimates for Killing graphs defined
over a complete manifold with nonempty boundary. To this end, we first point
out how the geometric analysis on a Killing graph is naturally related to a
weighted manifold structure, where the weight is defined in terms of the length
of the Killing vector field. According to this viewpoint, we introduce some
potential theory on weighted manifolds with boundary and we prove a weighted
volume estimate for intrinsic balls on the Killing graph. Finally, using these
tools, we provide the desired estimate for the weighted height in the
assumption that the Killing graph has constant weighted mean curvature and the
weighted geometry of the ambient space is suitably controlled.


title:
Electron Driven Mobility Model by Light on the Stacked
  Metal-Dielectric-Interfaces

abstract:
  An electron mobility enhancement is the very important phenomenon of an
electron in the electronic device, where the high electronic device performance
has the good electron mobility, which is obtained by the overall electron drift
velocity in the electronic material driven potential difference. The increasing
in electron mobility by the injected high group velocity pulse is proposed in
this article. By using light pulse input into the nonlinear microring
resonator, light pulse group velocity can be tuned and increased, from which
the required output group velocity can be obtained, which can be used to drive
electron within the plasmonic waveguide, where eventually, the relative
electron mobility can be obtained, the increasing in the electron mobility
after adding up by the driven optical fields can be connected to the external
electronic devices and circuits, which can be useful for many applications.


title: Quarkonium wave functions on the light front

abstract:
  We study heavy quarkonium within the light-front Hamiltonian formalism. Our
effective Hamiltonian is based on the holographic QCD confining potential and
the one-gluon exchange interaction with a running coupling. The obtained
spectra are compared with experimental measurements. We present a set of
light-front wave functions, which exhibit rich structure and are consistent
with the nonrelativistic picture. Finally, we use the wave functions to compute
the charge and mass radii.


title: Real-time Collision Handling in Railway Network:An Agent-based Approach

abstract:
  Advancement in intelligent transportation systems with complex operations
requires autonomous planning and management to avoid collisions in day-to-day
traffic. As failure and/or inadequacy in traffic safety system are
life-critical, such collisions must be detected and resolved in an efficient
way to manage continuously rising traffic. In this paper, we address different
types of collision scenarios along with their early detection and resolution
techniques in a complex railway system. In order to handle collisions
dynamically in distributed manner, a novel agent based solution approach is
proposed using the idea of max-sum algorithm, where each agent (train agent,
station agent, and junction agent) communicates and cooperates with others to
generate a good feasible solution that keeps the system in a safe state, i.e.,
collision free. We implement the proposed mechanism in Java Agent DEvelopment
Framework (JADE). The results are evaluated with exhaustive experiments and
compared with different existing collision handling methods to show the
efficiency of our proposed approach.


title:
Bright end of the luminosity function of high-mass X-ray binaries:
  contributions of hard, soft and supersoft sources

abstract:
  Using a spectral analysis of bright Chandra X-ray sources located in 27
nearby galaxies and maps of star-formation rate (SFR) and ISM surface densities
for these galaxies, we constructed the intrinsic X-ray luminosity function
(XLF) of luminous high-mass X-ray binaries (HMXBs), taking into account
absorption effects and the diversity of HMXB spectra. The XLF per unit SFR can
be described by a power law dN/d log L=2.0(L/10^39 erg/s)^(-0.6)
(M_Sun/yr)^(-1) from L=10^38 to 10^40.5 erg/s, where L is the unabsorbed
luminosity at 0.25-8 keV. The intrinsic number of luminous HMXBs per unit SFR
is a factor of ~2.3 larger than the observed number reported before. The
intrinsic XLF is composed of hard, soft and supersoft sources (defined here as
those with the 0.25-2 keV to 0.25-8 keV flux ratio of <0.6, 0.6-0.95 and >0.95,
respectively) in ~2:1:1 proportion. We also constructed the intrinsic HMXB XLF
in the soft X-ray band (0.25-2 keV). Here, the numbers of hard, soft and
supersoft sources prove to be nearly equal. The cumulative present-day 0.25-2
keV emissivity of HMXBs with luminosities between 10^38 and 10^40.5 erg/s is ~5
10^39 erg/s (M_Sun/yr)^(-1), which may be relevant for studying the X-ray
preheating of the early Universe.


title:
Preheating of the early Universe by radiation from high-mass X-ray
  binaries

abstract:
  Using a reliably measured intrinsic (i.e. corrected for absorption effects)
present-day luminosity function of high-mass X-ray binaries (HMXBs) in the
0.25-2 keV energy band per unit star-formation rate, we estimate the preheating
of the early Universe by soft X-rays from such systems. We find that X-ray
irradiation, mainly executed by ultraluminous and supersoft ultraluminous X-ray
sources with luminosity L> 10^39 erg/s, could significantly heat (T>T_cmb,
where T_cmb is the temperature of the cosmic microwave background) the
intergalactic medium by z~10 if the specific X-ray emissivity of the young
stellar population in the early Universe was an order of magnitude higher than
at the present epoch (which is possible due to the low metallicity of the first
galaxies) and the soft X-ray emission from HMXBs did not suffer strong
absorption within their galaxies. This makes it possible to observe the 21 cm
line of neutral hydrogen in emission from redshifts z<10.


title:
On the Complexity of the Quantified Bit-Vector Arithmetic with Binary
  Encoding

abstract:
  We study the precise computational complexity of deciding satisfiability of
first-order quantified formulas over the theory of fixed-size bit-vectors with
binary-encoded bit-widths and constants. This problem is known to be in
EXPSPACE and to be NEXPTIME-hard. We show that this problem is complete for the
complexity class AEXP(poly) -- the class of problems decidable by an
alternating Turing machine using exponential time, but only a polynomial number
of alternations between existential and universal states.


title: New Generation Value Networks for Content Delivery

abstract:
  In this paper we paint a broad picture of the Internet content delivery
market, by taking into consideration both economical and technical challenges
that might drive the interactions among the stakeholders in the future. We
focus on a few disrupting factors, namely ubiquitous encryption, traffic boost,
network scalability, latency needs and network control; and try to figure out
whether the current model (CDN) is robust against their variation, which
optimization can be envisioned and how the most accredited option (ICN) can be
of help.


title: Branching trees I: Concatenation and infinite divisibility

abstract:
  The goal of this work is to decompose random populations with a genealogy in
subfamilies of a given degree of kinship and to obtain a notion of infinitely
divisible genealogies. We model the genealogical structure of a population by
(equivalence classes of) ultrametric measure spaces (um-spaces) as elements of
the Polish space U which we recall. In order to then analyze the family
structure in this coding we introduce an algebraic structure on um-spaces (a
consistent collection of semigroups). This allows us to obtain a path of
collections of subfamilies of fixed kinship h (described as ultrametric measure
spaces), for every depth h as a measurable functional of the genealogy. Random
elements in the semigroup are studied, in particular infinitely divisible
random variables. Here we define infinite divisibility of random genealogies as
the property that the h-tops can be represented as concatenation of independent
identically distributed h-forests for every h and obtain a Levy-Khintchine
representation of this object and a corresponding representation via a
concatenation of points of a Poisson point process of h-forests. Finally the
case of discrete and marked um-spaces is treated allowing to apply the results
to both the individual based and most important spatial populations. The
results have various applications. In particular the case of the genealogical
(U-valued) Feller diffusion and genealogical (U V -valued) super random walk is
treated based on the present work in [DG18b] and [GRG]. In the part II of this
paper we go in a different direction and refine the study in the case of
continuum branching populations, give a refined analysis of the Laplace
functional and give a representation in terms of a Cox process on h-trees,
rather than forests.


title: Magnetism in f electron superlattices

abstract:
  We analyze antiferromagnetism in $f$ electron superlattices. We show that the
competition between the Kondo effect and the RKKY interaction in $f$ electron
materials is modified by the superlattice structure. Thus, the quantum critical
point which separates the magnetic phase and the Fermi liquid phase depends on
the structure of the $f$ electron superlattice. The competition between the
Kondo effect and the RKKY interaction is also reflected in the magnetic
interlayer coupling between different $f$ electron layers. We demonstrate that
in the case of weak Kondo effect the magnetic interlayer coupling behaves
similar to other magnetic heterostructures without Kondo effect. However, close
to the quantum phase transition, the dependence of the interlayer coupling on
the distance between the $f$ electron layers is modified by the Kondo effect.
Another remarkable effect, which is characteristic for $f$ electron
superlattice, is that the magnetic interlayer coupling does vanish stepwise
depending on the distance between different $f$ electron layers. As a
consequence, the quantum critical point depends also stepwise on this distance.


title:
Sharp $L^p$ estimates for Schr\"odinger groups on spaces of homogeneous
  type

abstract:
  We prove an $L^{p}$ estimate $$ \|e^{-itL} \varphi(L)f\|_{p}\lesssim
(1+|t|)^s\|f\|_p, \qquad t\in \mathbb{R}, \qquad
s=n\left|\frac{1}{2}-\frac{1}{p}\right| $$ for the Schr\"odinger group
generated by a semibounded, selfadjoint operator $L$ on a metric measure space
$\mathcal{X}$ of homogeneous type (where $n$ is the doubling dimension of
$\mathcal{X}$). The assumptions on $L$ are a mild $L^{p_{0}}\to L^{p_{0}'}$
smoothing estimate and a mild $L^{2}\to L^{2}$ off--diagonal estimate for the
corresponding heat kernel $e^{-tL}$. The estimate is uniform for $ \varphi$
varying in bounded sets of $\mathscr{S}(\mathbb{R})$, or more generally of a
suitable weighted Sobolev space. We also prove, under slightly stronger
assumptions on $L$, that the estimate extends to $$
  \|e^{-itL} \varphi(\theta L)f\|_{p}\lesssim (1+\theta^{-1}|t|)^s\|f\|_p,
  \qquad \theta>0, \quad t\in \mathbb{R}, $$ with uniformity also for $\theta$
varying in bounded subsets of $(0,+\infty)$. For nonnegative operators
uniformity holds for all $\theta>0$.


title:
Gain enhanced Fano resonance in a coupled photonic crystal
  cavity-waveguide structure

abstract:
  Systems with coupled cavities and waveguides have been demonstrated as
optical switches and optical sensors. To optimize the functionalities of these
optical devices, Fano resonance with asymmetric and steep spectral line shape
has been used. We theoretically propose a coupled photonic crystal
cavity-waveguide structure to achieve Fano resonance by placing partially
reflecting elements in waveguide. To enhance Fano resonance, optical gain
material is introduced into the cavity. As the gain increases, the transmission
line shape becomes steepened and the transmissivity can be six times enhanced,
giving a large contrast by a small frequency shift. It is prospected that the
gain enhanced Fano resonance is very useful for optical switches and optical
sensors.


title: Time Dependent Rindler Hamiltonian Eigen States in Momentum Space

abstract:
  We have developed a formalism to get the time evolution of the eigen states
of Rindler Hamiltonian in momentum space. We have shown the difficulties with
characteristic curves, and re-cast the time evolution equations in the form of
two-dimensional Laplace equation. The solutions are obtain both in polar
coordinates as well as in the Cartesian form.


title:
Effective field theory, electric dipole moments and electroweak
  baryogenesis

abstract:
  Negative searches for permanent electric dipole moments (EDMs) heavily
constrain models of baryogenesis utilising various higher dimensional charge
and parity violating (CPV) operators. Using effective field theory, we create a
model independent connection between these EDM constraints and the baryon
asymmetry of the universe (BAU) produced during a strongly first order
electroweak phase transition. The thermal aspects of the high scale physics
driving the phase transition are paramaterised by the usual kink solution for
the bubble wall profile. We find that operators involving derivatives of the
Higgs field yield CPV contributions to the BAU containing derivatives of the
Higgs vev, while non-derivative operators lack such contributions.
Consequently, derivative operators cannot be eliminated in terms of
non-derivative operators (via the equations of motion) if one is agnostic to
the new physics that leads to the phase transition. Thus, we re-classify the
independent dimension six operators, restricting ourselves to third generation
quarks, gauge bosons and the Higgs. Finally, we calculate the BAU (as a
function of the bubble wall width and the cutoff) for a derivative and a
non-derivative operator, and relate it to the EDM constraints.


title: A Short Proof of Euler--Poincar\'e Formula

abstract:
  "V - E + F = 2", the famous Euler's polyhedral formula, has a natural
generalization to convex polytopes in every finite dimension, also known as the
Euler-Poincar\'e Formula. We provide another short inductive proof of the
general formula. Our proof is self-contained and it does not use shellability
of polytopes.


title:
Cosmological solutions in spatially curved universes with adiabatic
  particle production

abstract:
  We perform a qualitative and thermodynamic study of two models when one takes
into account adiabatic particle production. In the first one, there is a
constant particle production rate, which leads to solutions depicting the
current cosmic acceleration but without inflation. The other one has solutions
that unify the early and late time acceleration. These solutions converge
asymptotically to the thermal equilibrium.


title:
Electronic structure study of vanadium spinels by using density
  functional theory and dynamical mean field theory

abstract:
  Theoretically, various physical properties of AV$_{2}$O$_{4}$ (A=Zn, Cd and
Mg) spinels have been extensively studied for last 15 years. Besides of this,
no systematic comparative study has been done for these compounds, where the
material specific parameters are used. Here, we report the comparative
electronic behaviour of these spinels by using a combination of density
functional theory and dynamical mean-field theory, where the self-consistent
calculated Coulomb interaction $U$ and Hund's coupling $J$ (determined by
Yukawa screening $\lambda$) are used. The main features, such as insulating
band gaps ($E_{g}$), degree of itinerancy of V 3$d$ electrons and position of
lower Hubbard band are observed for these parameters in these spinels. The
calculated values of $E_{g}$ for ZnV$_{2}$O$_{4}$, CdV$_{2}$O$_{4}$ and
MgV$_{2}$O$_{4}$ are found to be $\sim$0.9 eV, $\sim$0.95 eV and $\sim$1.15 eV,
respectively, where the values of $E_{g}$ are close to experiment for
ZnV$_{2}$O$_{4}$ and MgV$_{2}$O$_{4}$. The position of lower Hubbard band are
observed around $\sim$-1.05 eV, $\sim$-1.25 eV and $\sim$-1.15 eV for
ZnV$_{2}$O$_{4}$, CdV$_{2}$O$_{4}$ and MgV$_{2}$O$_{4}$, respectively, which
are also in good agreement with the experimental data for ZnV$_{2}$O$_{4}$. The
order of average impurity hybridization function of V site are found to be
ZnV$_{2}$O$_{4}$$>$MgV$_{2}$O$_{4}$$>$CdV$_{2}$O$_{4}$. Hence, the degree of
localization of V 3$d$ electrons is largest for CdV$_{2}$O$_{4}$ and smallest
for ZnV$_{2}$O$_{4}$, which is in accordance with our earlier results. Hence,
present work shows the importance of material specific parameters to understand
the comparative electronic behaviour of these compounds.


title: Haldane relation for interacting dimers

abstract:
  We consider a model of weakly interacting, close-packed, dimers on the
two-dimensional square lattice. In a previous paper, we computed both the
multipoint dimer correlations, which display non-trivial critical exponents,
continuously varying with the interaction strength; and the height
fluctuations, which, after proper coarse graining and rescaling, converge to
the massless Gaussian field with a suitable interaction-dependent pre-factor
(`amplitude'). In this paper, we prove the identity between the critical
exponent of the two-point dimer correlation and the amplitude of this massless
Gaussian field. This identity is the restatement, in the context of interacting
dimers, of one of the Haldane universality relations, part of his Luttinger
liquid conjecture, originally formulated in the context of one-dimensional
interacting Fermi systems. Its validity is a strong confirmation of the
effective massless Gaussian field description of the interacting dimer model,
which was guessed on the basis of formal bosonization arguments. We also
conjecture that a certain discrete curve defined at the lattice level via the
Temperley bijection converges in the scaling limit to an SLE$_\kappa$ process,
with $\kappa$ depending non-trivially on the interaction and related in a
simple way to the amplitude of the limiting Gaussian field.

categories: cond-mat.stat-mech math-ph math.MP math.PR


title:
Transfer matrix algorithm for computing the exact partition function of
  a square lattice polymer

abstract:
  I develop a transfer matrix algorithm for computing the exact partition
function of a square lattice polymer with nearest-neighbor interaction, by
extending a previous algorithm for computing the total number of self-avoiding
walks. The computation time scales as ~1.6^N with the chain length N, in
contrast to the explicit enumeration where the scaling is ~ 2.7^N. The exact
partition function can be obtained faster with the transfer matrix method than
with the explicit enumeration, for N>25. The new results for up to N=42 are
presented.


title: Toward a Tractable Delay Analysis in Ultra-dense Networks

abstract:
  Meeting the diverse delay requirements of emerging wireless applications is
one of the most critical goals for the design of ultradense networks. Though
the delay of point-to-point communications has been well investigated using
classical queueing theory, the delay of multi-point to multi-point
communications, such as in ultradense networks, has not been explored in depth.
The main technical difficulty lies in the interacting queues problem, in which
the service rate is coupled with the statuses of other queues. In this article,
we elaborate on the main challenges in the delay analysis in ultradense
networks. Several promising approaches, such as introducing the dominant system
and the simplified system, to bypass these difficulties are proposed and
summarized to provide useful guidance.


title: Cryptocurrency Portfolio Management with Deep Reinforcement Learning

abstract:
  Portfolio management is the decision-making process of allocating an amount
of fund into different financial investment products. Cryptocurrencies are
electronic and decentralized alternatives to government-issued money, with
Bitcoin as the best-known example of a cryptocurrency. This paper presents a
model-less convolutional neural network with historic prices of a set of
financial assets as its input, outputting portfolio weights of the set. The
network is trained with 0.7 years' price data from a cryptocurrency exchange.
The training is done in a reinforcement manner, maximizing the accumulative
return, which is regarded as the reward function of the network. Backtest
trading experiments with trading period of 30 minutes is conducted in the same
market, achieving 10-fold returns in 1.8 months' periods. Some recently
published portfolio selection strategies are also used to perform the same
back-tests, whose results are compared with the neural network. The network is
not limited to cryptocurrency, but can be applied to any other financial
markets.


title: Quantum bound to chaos and the semiclassical limit

abstract:
  We discuss the quantum bound on chaos in the context of the free propagation
of a particle in an arbitrarily curved surface at low temperatures. The
semiclassical calculation of the Lyapunov exponent can be performed in much the
same way as the corresponding one for the `Loschmidt echo'.The bound appears
here as the impossibility to scatter a wave, by effect of the curvature, over
characteristic lengths smaller than the deBroglie wavelength.


title:
Bloch Waves in Minimal Landau Gauge and the Infinite-Volume Limit of
  Lattice Gauge Theory

abstract:
  By exploiting the similarity between Bloch's theorem for electrons in
crystalline solids and the problem of Landau gauge-fixing in Yang-Mills theory
on a "replicated" lattice, one is able to obtain essentially infinite-volume
results from numerical simulations performed on a relatively small lattice.
This approach, proposed by D. Zwanziger in \cite{Zwanziger:1993dh}, corresponds
to taking the infinite-volume limit for Landau-gauge field configurations in
two steps: firstly for the gauge transformation alone, while keeping the
lattice volume finite, and secondly for the gauge-field configuration itself.
The solutions to the gauge-fixing condition are then given in terms of Bloch
waves. Applying the method to data from Monte Carlo simulations of pure SU(2)
gauge theory in two and three space-time dimensions, we are able to evaluate
the Landau-gauge gluon propagator for lattices of linear extent up to sixteen
times larger than that of the simulated lattice. The approach is reminiscent of
Fisher and Ruelle's construction of the thermodynamic limit in classical
statistical mechanics.


title:
Asteroseismic analysis of two alpha-enhanced stars KIC 7976303 and KIC
  8694723

abstract:
  We intent to use stellar models with and without alpha-enhancement, as well
as asteroseismic analysis, to study two alpha-enhanced stars, KIC 7976303 and
KIC 8694723. For the alpha-enhanced models, we adopt [alpha/Fe] = 0.2, and 0.4.
For the evolved sub-giant KIC 7976303 with mixed-modes, alpha-enhanced models
fit the observations better than the models without alpha-enhancement, and
point to a star with M = 1.20 $\pm$ 0.02 M_odot, t = 4.88 $\pm$ 0.08 Gyr, R =
2.04 $\pm$ 0.01 R_odot, and L = 5.07 $\pm$ 0.05 L_odot. For the post turnoff
star KIC 8694723, we find that the models fit the observations well in all
three cases ([alpha/Fe] = 0.0, 0.2, 0.4). According to the observed metal
abundances, only alpha- enhanced models are used to estimate the stellar
parameters, which are M = 1.13 $\pm$ 0.06 M_odot, t = 5.47 $\pm$ 0.43 Gyr, R =
1.55 $\pm$ 0.13 R_odot, and L = 3.18 $\pm$ 0.26 L_odot. Our alpha-enhanced
models indicate KIC 7976303 has a larger mass and younger age than in previous
works based on standard models. Furthermore, the differences of estimated mass
and age between the three cases are $\sim$ 0.1 M_odot and $\sim$ 0.5 - 1.3 Gyr.
These results suggest that we include alpha-enhancement in the modeling of
alpha-enhanced stars, such as members of GCs (Globular Clusters), metal-poor
stars in the disc and in the halo.


title:
Characterization of Novel Thin N-in-P Planar Pixel Modules for the ATLAS
  Inner Tracker Upgrade

abstract:
  The ATLAS experiment will undergo a major upgrade of the tracker system in
view of the high luminosity phase of the LHC (HL-LHC) to start operation in
2026. The most severe challenges are to be faced by the innermost layers of the
pixel detector which will have to withstand a radiation fluence of up to
$1.4\times10^{16}\,$n$_\text{eq}$/cm$^{2}$. Thin planar pixel modules are
promising candidates to instrument these layers, thanks to the small material
budget and their high charge collection efficiency after irradiation. Sensors
of $100-200\,\mu$m thickness, interconnected to FE-I4 read-out chips, are
characterized with radioactive sources as well as testbeams at the CERN-SPS and
DESY. The performance of sensors irradiated up to a fluence of $5\times
10^{15}\,$n$_\text{eq}$/cm$^{2}$ is compared in terms of charge collection and
hit efficiency. Highly segmented sensors are a challenge for the tracking in
the forward region of the pixel system at the HL-LHC. To reproduce the
performance of $50$x$50\,\mu$m$^2$ pixels at high pseudo-rapidities, FE-I4
compatible planar pixel sensors are studied before and after irradiation in
beam tests at high incidence angle ($80^\circ$) with respect to the short pixel
direction. Results on cluster shape and hit efficiency will be shown.


title: In-network Compression for Multiterminal Cascade MIMO Systems

abstract:
  We study the problem of receive beamforming in uplink cascade multiple-input
multiple-output (MIMO) systems as an instance of that of cascade multiterminal
source coding for lossy function computation. Using this connection, we develop
two coding schemes for the second and show that their application leads to
beamforming schemes for the first. In the first coding scheme, each terminal in
the cascade sends a description of the source that it observes; the decoder
reconstructs all sources, lossily, and then computes an estimate of the desired
function. This scheme improves upon standard routing in that every terminal
only compresses the innovation of its source w.r.t. the descriptions that are
sent by the previous terminals in the cascade. In the second scheme, the
desired function is computed gradually in the cascade network, and each
terminal sends a finer description of it. In the context of uplink cascade MIMO
systems, the application of these two schemes leads to centralized
receive-beamforming and distributed receive-beamforming, respectively.
Numerical results illustrate the performance of the proposed methods and show
that they outperform standard routing.


title: Formation of satellites from cold collapse

abstract:
  We study the collapse of an isolated, initially cold, irregular (but almost
spherical) and (slightly) inhomogeneous cloud of self-gravitating particles.
The cloud is driven towards a virialized quasi-equilibrium state by a fast
relaxation mechanism, occurring in a typical time $\tau_c$, whose signature is
a large change in the particle energy distribution. Post-collapse particles are
divided into two main species: bound and free, the latter being ejected from
the system. Because of the initial system's anisotropy, the time varying
gravitational field breaks spherical symmetry so that the ejected mass can
carry away angular momentum and the bound system can gain a non-zero angular
momentum. In addition, while strongly bound particles form a compact core,
weakly bound ones may form, in a time scale of the order of $\tau_c$, several
satellite sub-structures. These satellites have a finite lifetime that can be
longer than $\tau_c$ and generally form a flattened distribution. Their origin
and their abundance are related to the amplitude and nature of initial density
fluctuations and to the initial cloud deviations from spherical symmetry, which
are both amplified during the collapse phase. Satellites show a time dependent
virial ratio that can be different from the equilibrium value $b\approx -1$:
although they are bound to the main virialized object, they are not necessarily
virially relaxed.


title: Modeling Structure and Resilience of the Dark Network

abstract:
  While the statistical and resilience properties of the Internet are no more
changing significantly across time, the Darknet, a network devoted to keep
anonymous its traffic, still experiences rapid changes to improve the security
of its users. Here, we study the structure of the Darknet and we find that its
topology is rather peculiar, being characterized by non-homogenous distribution
of connections -- typical of scale-free networks --, very short path lengths
and high clustering -- typical of small-world networks -- and lack of a core of
highly connected nodes.
  We propose a model to reproduce such features, demonstrating that the
mechanisms used to improve cyber-security are responsible for the observed
topology. Unexpectedly, we reveal that its peculiar structure makes the Darknet
much more resilient than the Internet -- used as a benchmark for comparison at
a descriptive level -- to random failures, targeted attacks and cascade
failures, as a result of adaptive changes in response to the attempts of
dismantling the network across time.


title: A Fully Discrete Galerkin Method for Abel-type Integral Equations

abstract:
  In this paper, we present a Galerkin method for Abel-type integral equation
with a general class of kernel. Stability and quasi-optimal convergence
estimates are derived in ractional-order Sobolev norms. The fully-discrete
Galerkin method is defined by employing simple tensor-Gauss quadrature. We
develop a corresponding perturbation analysis which allows to keep the number
of quadrature points small. Numerical experiments have been performed which
illustrate the sharpness of the theoretical estimates and the sensitivity of
the solution with respect to some parameters in the equation.


title:
Development of a Watt-level Gamma-Ray Source based on
  High-Repetition-Rate Inverse Compton Scattering

abstract:
  A high-brilliance ($\sim10^{24}$~photon.s$^{-1}$.mm$^{-2}$.mrd$^{-2}$/0.1\%)
gamma-ray source experiment is currently being planned at Fermilab
($E_\gamma\simeq 1.1$~MeV)~[1]. The source implements a high-repetition-rate
inverse Compton scattering by colliding electron bunches formed in a 300-MeV
superconducting linac with a high-intensity laser pulse. This paper describes
the design rationale along with some of technical challenges associated to
producing high-repetition-rate collision. The expected performances of the
gamma-ray source are also presented.


title:
High-order quadrature-based lattice Boltzmann models for the flow of
  ultrarelativistic rarefied gases

abstract:
  We present a systematic procedure for the construction of relativistic
lattice Boltzmann models (R-SLB) appropriate for the simulation of flows of
massless particles. Quadrature rules are used for the discretization of the
momentum space in spherical coordinates. The models are optimized for
one-dimensional flows. The applications considered in this paper are the Sod
shock tube and the one-dimensional boost invariant expansion (Bjorken flow).
Our models are tested against exact solutions in the inviscid and ballistic
limits. At intermediate relaxation times (finite viscosity), we compare with
the results obtained using the Boltzmann approach of multiparton scattering
model for the Sod shock tube problem, as well as with a semi-analytic solution
for the non-ideal Bjorken flow. In all cases our models give remarkably good
results. We define a convergence test in order to find the quadrature order
necessary to obtain convergence at a predefined accuracy. We show that, while
in the hydrodynamic regime the number of velocities is comparable to that
required for the more popular collision-streaming type models, as we go towards
the ballistic regime, the size of the velocity set must be substantially
increased in order to accurately reproduce the analytic profiles.


title: Point Pair Feature based Object Detection for Random Bin Picking

abstract:
  Point pair features are a popular representation for free form 3D object
detection and pose estimation. In this paper, their performance in an
industrial random bin picking context is investigated. A new method to generate
representative synthetic datasets is proposed. This allows to investigate the
influence of a high degree of clutter and the presence of self similar
features, which are typical to our application. We provide an overview of
solutions proposed in literature and discuss their strengths and weaknesses. A
simple heuristic method to drastically reduce the computational complexity is
introduced, which results in improved robustness, speed and accuracy compared
to the naive approach.


title:
Wilson chiral perturbation theory for dynamical twisted mass fermions vs
  lattice data - a case study

abstract:
  We compute the low lying eigenvalues of the Hermitian Dirac operator in
lattice QCD with $N_{\rm f} = 2+1+1$ twisted mass fermions. We discuss whether
these eigenvalues are in the $\epsilon$-regime or the $p$-regime of Wilson
chiral perturbation theory ($\chi$PT) for twisted mass fermions. Reaching the
deep $\epsilon$-regime is practically unfeasible with presently typical
simulation parameters, but still the few lowest eigenvalues of the employed
ensemble evince some characteristic $\epsilon$-regime features. With this
conclusion in mind, we develop a fitting strategy to extract two low energy
constants from analytical $\epsilon$-regime predictions at a fixed index. Thus,
we obtain results for the chiral condensate and the low energy constant $W_8$.
We also discuss how to improve both the theoretical calculation and the lattice
computation.


title: Entire holomorphic curves on a Fermat surface of low degree

abstract:
  The purpose of the paper is to study some problems raised by Hayman and
Gundersen about the existence of non-trivial entire and meromorphic solutions
for the Fermat type functional equation $f^n+g^n+h^n=1$. Hayman showed that no
non-trivial meromorphic solutions and entire solutions exist when $n \ge 9$ and
$n \ge 7$ respectively. By considering the entire holomorphic curves on the
Fermat surface defined by $X^n+Y^n+Z^n=W^n$ on the complex projective space
$\mathbb{P}^3$ and applying the method of jet differentials, we show that no
non-trivial meromorphic solutions and entire solutions exist when $n \ge 8$ and
$n \ge 6$ respectively. In particular, this completes the investigation of
non-trivial entire solutions for all $n$ and respectively, meromorphic
solutions for all cases except for $n=7$. Finally, for the generalized Fermat
type functional equation $f^n+g^m+h^l=1$, we will also prove the non-existence
of non-trivial meromorphic solutions when $1/n+1/m+1/l \le 3/8$, giving the
strongest result obtained so far.


title:
Models for the assessment of treatment improvement: the ideal and the
  feasible

abstract:
  Comparisons of different treatments or production processes are the goals of
a significant fraction of applied research. Unsurprisingly, two-sample problems
play a main role in Statistics through natural questions such as `Is the the
new treatment significantly better than the old?'. However, this is only
partially answered by some of the usual statistical tools for this task. More
importantly, often practitioners are not aware of the real meaning behind these
statistical procedures. We analyze these troubles from the point of view of the
order between distributions, the stochastic order, showing evidence of the
limitations of the usual approaches, paying special attention to the classical
comparison of means under the normal model. We discuss the unfeasibility of
statistically proving stochastic dominance, but show that it is possible,
instead, to gather statistical evidence to conclude that slightly relaxed
versions of stochastic dominance hold.


title: Vertex algebras and quantum master equation

abstract:
  We study the effective Batalin-Vilkovisky quantization theory for chiral
deformation of two dimensional conformal field theories. We establish an exact
correspondence between renormalized quantum master equations for effective
functionals and Maurer-Cartan equations for chiral vertex operators. The
generating functions are proven to have modular property with mild holomorphic
anomaly. As an application, we construct an exact solution of quantum B-model
(BCOV theory) in complex one dimension that solves the higher genus mirror
symmetry conjecture on elliptic curves.


title:
Towards semi-inclusive deep inelastic scattering at
  next-to-next-to-leading order

abstract:
  In this paper, we compute the first set of ${\cal O}(\alpha_s^2)$ corrections
to semi-inclusive deep inelastic scattering structure functions. We start by
studying the impact of the contribution of the partonic subprocesses that open
at this order for the longitudinal structure function. We perform the full
calculation analytically, and obtain the expression of the factorized cross
section at this order. Special care is given to the study of their flavour
decomposition structure. We analyze the phenomenological effect of the
corrections finding that, even though expected to be small a priori, it turns
out to be sizable with respect to the previous order know, calling for a full
NNLO calculation.


title: Message Passing Multi-Agent GANs

abstract:
  Communicating and sharing intelligence among agents is an important facet of
achieving Artificial General Intelligence. As a first step towards this
challenge, we introduce a novel framework for image generation: Message Passing
Multi-Agent Generative Adversarial Networks (MPM GANs). While GANs have
recently been shown to be very effective for image generation and other tasks,
these networks have been limited to mostly single generator-discriminator
networks. We show that we can obtain multi-agent GANs that communicate through
message passing to achieve better image generation. The objectives of the
individual agents in this framework are two fold: a co-operation objective and
a competing objective. The co-operation objective ensures that the message
sharing mechanism guides the other generator to generate better than itself
while the competing objective encourages each generator to generate better than
its counterpart. We analyze and visualize the messages that these GANs share
among themselves in various scenarios. We quantitatively show that the message
sharing formulation serves as a regularizer for the adversarial training.
Qualitatively, we show that the different generators capture different traits
of the underlying data distribution.


title: Extremal regular graphs: the case of the infinite regular tree

abstract:
  In this paper we study the following problem. Let $A$ be a fixed graph, and
let $\hom(G,A)$ denote the number of homomorphisms from a graph $G$ to $A$.
Furthermore, let $v(G)$ denote the number of vertices of $G$, and let
$\mathcal{G}_d$ denote the family of $d$--regular graphs. The general problem
studied in this paper is to determine $$\inf_{G\in
\mathcal{G}_d}\hom(G,A)^{1/v(G)}.$$ It turns out that in many instances the
infimum is not achieved by a finite graph, but a sequence of graphs with girth
(i. e., length of the shortest cycle) tending to infinity. In other words, the
optimization problem is solved by the infinite $d$--regular tree.
  We prove this type of results for the number of independent sets of bipartite
graphs, evaluations of the Tutte-polynomial, Widom-Rowlinson configurations,
and many more graph parameters. Our main tool will be a transformation called
$2$-lift.


title: Conformal anomalies and the Einstein Field Equations

abstract:
  We compute corrections to the Einstein field equations which are induced by
the anomalous effective actions associated to the type A conformal anomaly,
both for the (non-local) Riegert action, as well as for the local action with
dilaton. In all cases considered we find that these corrections can be very
large.


title:
Backward problems for stochastic differential equations on the
  Sierpinski gasket

abstract:
  In this paper, we study the non-linear backward problems (with deterministic
or stochastic durations) of stochastic differential equations on the Sierpinski
gasket. We prove the existence and uniqueness of solutions of backward
stochastic differential equations driven by Brownian martingale (defined in
Section [sec:-1]) on the Sierpinski gasket constructed by S. Goldstein and S.
Kusuoka. The exponential integrability of quadratic processes for martingale
additive functionals is obtained, and as an application, a Feynman-Kac
representation formula for weak solutions of semi-linear parabolic PDEs on the
gasket is also established.


title: On the hysteresis behaviors of the higher spin Ising model

abstract:
  Hysteresis characteristics of the general Spin-S ($S>1$) Blume-Capel model
have been studied within the effective field approximation. Particular emphasis
has been paid on the large negative valued crystal field region and it has been
demonstrated for this region that, Spin-S Blume-Capel model has $2S$ windowed
hysteresis loop in low temperatures. Some interesting results have been
obtained such as nested characteristics of the hysteresis loops of successive
spin-S Blume-Capel model. Effect of the rising crystal field and temperature on
these hysteresis behaviors have been investigated in detail and physical
mechanisms have been given.


title: Noether Symmetry Approach in $f(T,B)$ teleparallel cosmology

abstract:
  We consider the cosmology derived from $f(T,B)$ gravity where $T$ is the
torsion scalar and $B=\frac{2}{e}\partial_{\mu}(e T^{\mu})$ a boundary term. In
particular we discuss how it is possible to recover, under the same standard,
the teleparallel $f(T)$ gravity, the curvature $f(R)$ gravity and the
teleparallel-curvature $f(R,T)$ gravity, which are particular cases of
$f(T,B)$. We adopt the Noether Symmetry Approach to study the related dynamical
systems and to find out cosmological solutions.


title:
Regular functions on spherical nilpotent orbits in complex symmetric
  pairs: classical Hermitian cases

abstract:
  Given a classical semisimple complex algebraic group G and a symmetric pair
(G,K) of Hermitian type, we study the closures of the spherical nilpotent
K-orbits in the isotropy representation of K. We show that all such orbit
closures are normal and describe the K-module structure of their ring of
regular functions.


title: On fractional p-laplacian parabolic problem with general data

abstract:
  In this article the problem to be studied is the following $$ (P) \left\{
\begin{array}{rcll} u_t+(-\D^s_{p}) u & = & f(x,t) & \text{ in } \O_{T}\equiv
\Omega \times (0,T), \\ u & = & 0 & \text{ in }(\ren\setminus\O) \times (0,T),
\\ u & \ge & 0 & \text{ in }\ren \times (0,T),\\ u(x,0) & = & u_0(x) & \mbox{
in }\O, \end{array}% \right. $$ where $\Omega$ is a bounded domain, and
$(-\D^s_{p})$ is the fractional p-Laplacian operator defined by $$
(-\D^s_{p})\, u(x,t):=P.V\int_{\ren}
\,\dfrac{|u(x,t)-u(y,t)|^{p-2}(u(x,t)-u(y,t))}{|x-y|^{N+ps}} \,dy$$ with
$1<p<N$, $s\in (0,1)$ and $f, u_0$ are measurable functions.
  The main goal of this work is to prove that if $(f,u_0)\in L^1(\O_T)\times
L^1(\O)$, problem $(P)$ has a weak solution with suitable regularity. In
addition, if $f_0, u_0$ are nonnegative, we show that the problem above has a
nonnegative entropy solution.
  In the case of nonnegative data, we give also some quantitative and
qualitative properties of the solution according the values of $p$.


title: A Primer on Portfolio Choice with Small Transaction Costs

abstract:
  This survey is an introduction to asymptotic methods for portfolio-choice
problems with small transaction costs. We outline how to derive the
corresponding dynamic programming equations and simplify them in the small-cost
limit. This allows to obtain explicit solutions in a wide range of settings,
which we illustrate for a model with mean-reverting expected returns and
proportional transaction costs. For even more complex models, we present a
policy iteration scheme that allows to compute the solution numerically.


title: Valuations and curvature measures on complex spaces

abstract:
  We survey recent results in hermitian integral geometry, i.e. integral
geometry on complex vector spaces and complex space forms. We study valuations
and curvature measures on complex space forms and describe how the global and
local kinematic formulas on such spaces were recently obtained. While the local
and global kinematic formulas in the Euclidean case are formally identical, the
local formulas in the hermitian case contain strictly more information than the
global ones. Even if one is only interested in the flat hermitian case, i.e.
$\mathbb C^n$, it is necessary to study the family of all complex space forms,
indexed by the holomorphic curvature $4\lambda$, and the dependence of the
formulas on the parameter $\lambda$. We will also describe Wannerer's recent
proof of local additive kinematic formulas for unitarily invariant area
measures.


title:
Galaxy Evolution at High Redshift: Obscured Star Formation, GRB Rates,
  Cosmic Reionization, and Missing Satellites

abstract:
  We provide an holistic view of galaxy evolution at high redshift z>4, that
incorporates the constraints from various astrophysical/cosmological probes,
including the estimate of the cosmic SFR density from UV/IR surveys and long
GRB rates, the cosmic reionization history after the latest Planck
measurements, and the missing satellites issue. We achieve this goal in a
model-independent way by exploiting the SFR functions derived by Mancuso et al.
(2016) on the basis of an educated extrapolation of the latest UV/far-IR data
from HST/Herschel, and already tested against a number of independent
observables. Our SFR functions integrated down to an UV magnitude limit
M_UV<-13 (or SFR limit around 10^-2 M_sun/yr) produces a cosmic SFR density in
excellent agreement with recent determinations from IR surveys and, taking into
account a metallicity ceiling Z<Z_sun/2, with the estimates from long GRB
rates. They also yield a cosmic reionization history consistent with that
implied by the recent measurements of the Planck mission on the electron
scattering optical depth tau_es~0.058; remarkably, this result is obtained
under a conceivable assumption regarding the average value f_esc~0.1 of the
escape fraction for ionizing photons. We demonstrate via the abundance matching
technique that the above constraints concurrently imply galaxy formation to
become inefficient within dark matter halos of mass below a few 10^8 M_sun;
pleasingly, such a limit is also required not to run into the missing satellite
issue. Finally, we predict a downturn of the galaxy luminosity function
faintward of M_UV<-12, and stress that its detailed shape, as plausibly probed
in the next future by the JWST, will be extremely informative on the
astrophysics of galaxy formation in small halos, or even on the microscopic
nature of the dark matter.


title:
Denoising of gravitational wave signals via dictionary learning
  algorithms

abstract:
  Gravitational wave astronomy has become a reality after the historical
detections accomplished during the first observing run of the two advanced LIGO
detectors. In the following years, the number of detections is expected to
increase significantly with the full commissioning of the advanced LIGO,
advanced Virgo and KAGRA detectors. The development of sophisticated data
analysis techniques to improve the opportunities of detection for low
signal-to-noise-ratio events is hence a most crucial effort. We present in this
paper one such technique, dictionary-learning algorithms, which have been
extensively developed in the last few years and successfully applied mostly in
the context of image processing. However, to the best of our knowledge, such
algorithms have not yet been employed to denoise gravitational wave signals. By
building dictionaries from numerical relativity templates of both, binary black
holes mergers and bursts of rotational core collapse, we show how
machine-learning algorithms based on dictionaries can be also successfully
applied for gravitational wave denoising. We use a subset of signals from both
catalogs, embedded in non-white Gaussian noise, to assess our techniques with a
large sample of tests and to find the best model parameters. The application of
our method to the actual signal GW150914 shows promising results.
Dictionary-learning algorithms could be a complementary addition to the
gravitational wave data analysis toolkit. They may be used to extract signals
from noise and to infer physical parameters if the data are in good enough
agreement with the morphology of the dictionary atoms.


title: Scattering in three-dimensional fuzzy space

abstract:
  We develop scattering theory in a non-commutative space defined by a $su(2)$
coordinate algebra. By introducing a positive operator valued measure as a
replacement for strong position measurements, we are able to derive explicit
expressions for the probability current, differential and total cross-sections.
We show that at low incident energies the kinematics of these expressions is
identical to that of commutative scattering theory. The consequences of spacial
non-commutativity are found to be more pronounced at the dynamical level where,
even at low incident energies, the phase shifts of the partial waves can
deviate strongly from commutative results. This is demonstrated for scattering
from a spherical well. The impact of non-commutativity on the well's spectrum
and on the properties of its bound and scattering states are considered in
detail. It is found that for sufficiently large well-depths the potential
effectively becomes repulsive and that the cross-section tends towards that of
hard sphere scattering. This can occur even at low incident energies when the
particle's wave-length inside the well becomes comparable to the
non-commutative length-scale.


title:
Density estimates for $k$-impassable lattices of balls and general
  convex bodies in ${\Bbb R}^n$

abstract:
  G. Fejes T\'oth posed the following problem: Determine the infimum of the
densities of the lattices of closed balls in $\bR^n$ such that each affine
$k$-subspace $(0 \le k \le n-1)$ of $\bR^n$ intersects some ball of the
lattice. We give a lower estimate for any $n,k$ like above. If, in the problem
posed by G. Fejes T\'oth, we replace the ball $B^n$ by a (centrally symmetric)
convex body $K\subset \bR^n$, we may ask for the infimum of all above infima of
densities of lattices of translates of $K$ with the above property, when $K$
ranges over all (centrally symmetric) convex bodies in $\bR^n$. For these
quantities we give lower estimates as well, which are sharp, or almost sharp,
for certain classes of convex bodies $K$. For $k=n-1$ we give an upper estimate
for the supremum of all above infima of densities, $K$ also ranging as above
(i.e., a "minimax" problem). For $n=2$ our estimate is rather close to the
conjecturable maximum. We point out the connection of the above questions to
the following problem: Find the largest radius of a cylinder, with base an
$(n-1)$-ball, that can be fitted into any lattice packing of balls (actually,
here balls can be replaced by some convex bodies $K \subset \bR^n$, the axis of
the cylinder may be $k$-dimensional and its basis has to be chosen suitably).
Among others we complete the proof of a theorem of I. Hortob\'agyi from 1971.
Our proofs for the lower estimates of densities for balls, and for the cylinder
problem, follow quite closely a paper of J. Horv\'ath from 1970. This paper is
also an addendum to a paper of the first named author from 1978 in the sense
that to some arguments given there not in a detailed manner, we give here for
all of these complete proofs.


title:
Towards differential geometric characterization of slow invariant
  manifolds in extended state space: Sectional Curvature and Flow Invariance

abstract:
  Some model reduction techniques for multiple time-scale dynamical systems
make use of the identification of low dimensional slow invariant attracting
manifolds (SIAM) in order to reduce the dimensionality of the phase space by
restriction to the slow flow. The focus of this work is on a proposition and
discussion of a general viewpoint using differential geometric concepts for
submanifolds to deal with slow invariant manifolds in an extended phase space.
The motivation is a coordinate independent formulation of the manifold
properties and its characterization problem treating the manifold as intrinsic
geometric object. We formulate a computationally verifiable necessary condition
for the slow invariant manifold graph stated in terms of a differential
geometric view on the invariance property. Its application to example systems
is illustrated. In addition, we present some ideas and investigations
concerning the search for sufficient, differential geometric conditions
characterizing slow invariant manifolds based on our previously developed
variational principle.


title: The N2HDM under Theoretical and Experimental Scrutiny

abstract:
  The N2HDM is based on the CP-conserving 2HDM extended by a real scalar
singlet field. Its enlarged parameter space and its fewer symmetry conditions
as compared to supersymmetric models allow for an interesting phenomenology
compatible with current experimental constraints, while adding to the 2HDM
sector the possibility of Higgs-to-Higgs decays with three different Higgs
bosons. In this paper the N2HDM is subjected to detailed scrutiny. Regarding
the theoretical constraints we implement tests of tree-level perturbativity and
vacuum stability. Moreover, we present, for the first time, a thorough analysis
of the global minimum of the N2HDM. The model and the theoretical constraints
have been implemented in ScannerS, and we provide N2HDECAY, a code based on
HDECAY, for the computation of the N2HDM branching ratios and total widths
including the state-of-the-art higher order QCD corrections and off-shell
decays. We then perform an extensive parameter scan in the N2HDM parameter
space, with all theoretical and experimental constraints applied, and analyse
its allowed regions. We find that large singlet admixtures are still compatible
with the Higgs data and investigate which observables will allow to restrict
the singlet nature most effectively in the next runs of the LHC. Similarly to
the 2HDM, the N2HDM exhibits a wrong-sign parameter regime, which will be
constrained by future Higgs precision measurements.


title: Symmetry breaking in a globally coupled map of four sites

abstract:
  A system of four globally coupled doubling maps is studied in this paper. It
is known that such systems have a unique absolutely continuous invariant
measure (acim) for weak interaction, but the case of stronger coupling is still
unexplored. As in the case of three coupled sites, we prove the existence of a
critical value of the coupling parameter at which multiple acims appear. Our
proof has several new ingredients in comparison to the one presented in our
previous paper regarding the system of three sites. We strongly exploit the
symmetries of the dynamics in the course of the argument. This simplifies the
computations considerably, and gives us a precise description of the geometry
and symmetry properties of the arising asymmetric invariant sets. Some new
phenomena are observed which are not present in the case of three sites. In
particular, the asymmetric invariant sets arise in areas of the phase space
which are transient for weaker coupling and a nontrivial symmetric invariant
set emerges, shaped by an underlying centrally symmetric Lorenz map. We state
some conjectures on further invariant sets, indicating that unlike the case of
three sites, ergodicity breaks down in many steps, and not all of them are
accompanied by symmetry breaking.


title:
Self-similar formation of the Kolmogorov spectrum in the Leith model of
  turbulence

abstract:
  The last stage of evolution toward the stationary Kolmogorov spectrum of
hydrodynamic turbulence is studied using the Leith model. This evolution is
shown to manifest itself as a reflection wave in the wavenumber space
propagating from the largest toward the smallest wavenumbers, and is described
by a self-similar solution of a new (third) kind. This stage follows the
previously studied stage of an initial explosive propagation of the spectral
front from the smallest to the largest wavenumbers reaching arbitrarily large
wavenumbers in a finite time, and which was described by a self-similar
solution of the second kind. Nonstationary solutions corresponding to"warm
cascades" characterised by a thermalised spectrum at large wavenumbers are also
obtained.


title: Parabolic inductions for pro-$p$-Iwahori Hecke algebras

abstract:
  We give some properties of parabolic inductions and their adjoint functors
for pro-$p$-Iwahori Hecke algebras.


title: On the Capacity of Discrete-Time Laguerre Channel

abstract:
  In this paper, new upper and lower bounds are proposed for the capacity of
discrete-time Laguerre channel. Laguerre behavior is used to model various
types of optical systems and networks such as optical amplifiers, short
distance visible light communication systems with direct detection and coherent
code division multiple access (CDMA) networks. Bounds are derived for short
distance visible light communication systems and coherent CDMA networks. These
bounds are separated in three main cases: when both average and peak power
constraints are imposed, when peak power constraint is inactive and when only
peak power constraint is active.


title:
Fabrication of ice-templated tubes by rotational freezing:
  microstructure, strength, and permeability

abstract:
  We demonstrate a facile and scalable technique, rotational freezing, to
produce porous tubular ceramic supports with radially aligned porosity. The
method is based on a conventional ice-templating process in a rotatory mold and
demonstrated here with yttria-stabilized zirconia (YSZ). We investigated the
effects of solid loading, freezing temperature, and volume of the slurry on the
microstructure, strength (o-ring test and four-point bending), and air
permeability. The results show that pore volume and pore size can be controlled
by the solid loading and freezing temperature respectively, and overall tube
thickness can be adjusted by the volume of slurry initially poured into the
mold. Decreasing pore size and pore volume increases the mechanical properties
but decreases the air permeability. These tubes could be particularly
interesting as tubular membrane supports such as oxygen transport membranes.


title: On generalized Latt\`es maps

abstract:
  We introduce a class of rational functions $A:\,\mathbb C\mathbb
P^1\rightarrow \mathbb C\mathbb P^1$ which can be considered as a natural
extension of the class of Latt\`es maps and establish basic properties of
functions from this class.


title: Ranking Biomarkers Through Mutual Information

abstract:
  We study information theoretic methods for ranking biomarkers. In clinical
trials there are two, closely related, types of biomarkers: predictive and
prognostic, and disentangling them is a key challenge. Our first step is to
phrase biomarker ranking in terms of optimizing an information theoretic
quantity. This formalization of the problem will enable us to derive rankings
of predictive/prognostic biomarkers, by estimating different, high dimensional,
conditional mutual information terms. To estimate these terms, we suggest
efficient low dimensional approximations, and we derive an empirical Bayes
estimator, which is suitable for small or sparse datasets. Finally, we
introduce a new visualisation tool that captures the prognostic and the
predictive strength of a set of biomarkers. We believe this representation will
prove to be a powerful tool in biomarker discovery.


title: Evolution of redback radio pulsars in globular clusters

abstract:
  We study the evolution of close binary systems composed of a normal,
intermediate mass star and a neutron star considering a chemical composition
typical of that present in globular clusters (Z = 0.001). We look for
similarities and differences with respect to solar composition donor stars,
which we have extensively studied in the past. As a definite example, we
perform an application on one of the redbacks located in a globular cluster. We
performed a detailed grid of models in order to find systems that represent the
so-called redback binary radio pulsar systems with donor star masses between
0.6 and 2.0 solar masses and orbital periods in the range 0.2 - 0.9 days. We
find that the evolution of these binary systems is rather similar to those
corresponding to solar composition objects, allowing us to account for the
occurrence of redbacks in globular clusters, as the main physical ingredient is
the irradiation feedback. Redback systems are in the quasi-RLOF state, that is,
almost filling their corresponding Roche lobe. During the irradiation cycle the
system alternates between semi-detached and detached states. While detached the
system appears as a binary millisecond pulsar, called a redback. Circumstellar
material, as seen in redbacks, is left behind after the previous semi-detached
phase. The evolution of binary radio pulsar systems considering irradiation
successfully accounts for, and provides a way for, the occurrence of redback
pulsars in low-metallicity environments such as globular clusters. This is the
case despite possible effects of the low metal content of the donor star that
could drive systems away from redback configuration.


title: Geometry on the lines of spine spaces

abstract:
  Spine spaces can be considered as fragments of a projective Grassmann space.
We prove that the structure of lines together with binary coplanarity relation,
as well as with binary relation of being in one pencil of lines, is a
sufficient system of primitive notions for these geometries. It is also shown
that, over a spine space, the geometry of pencils of lines can be reconstructed
in terms of the two binary relations.


title: Clifford Coherent State Transforms on Spheres

abstract:
  We introduce a one-parameter family of transforms, $U^t_{(m)}$, $t>0$, from
the Hilbert space of Clifford algebra valued square integrable functions on the
$m$--dimensional sphere, $L^2(S^{m},d\sigma_{m})\otimes \mathbb{C}_{m+1}$, to
the Hilbert spaces, ${\mathcal M}L^2(\mathbb{R}^{m+1} \setminus \{0\},d\mu_t)$,
of monogenic functions on $\mathbb{R}^{m+1}\setminus \{0\}$ which are square
integrable with respect to appropriate measures, $d\mu_t$. We prove that these
transforms are unitary isomorphisms of the Hilbert spaces and are extensions of
the Segal-Bargman coherent state transform, $U_{(1)} : L^2(S^{1},d\sigma_{1})
\longrightarrow {\mathcal H}L^2({\mathbb{C} \setminus \{0\}},d\mu)$, to higher
dimensional spheres in the context of Clifford analysis. In Clifford analysis
it is natural to replace the analytic continuation from $S^m$ to
$S^m_{\mathbb{C}}$ as in \cite{Ha1, St, HM} by the Cauchy--Kowalewski extension
from $S^m$ to $\mathbb{R}^{m+1}\setminus \{0\}$. One then obtains a unitary
isomorphism from an $L^2$--Hilbert space to an Hilbert space of solutions of
the Dirac equation, that is to a Hilbert space of monogenic functions.


title: Root multiplicities for Borcherds algebras and graph coloring

abstract:
  We establish a connection between root multiplicities for Borcherds-Kac-Moody
algebras and graph coloring. We show that the generalized chromatic polynomial
of the graph associated to a given Borcherds algebra can be used to give a
closed formula for certain root multiplicities. Using this connection we give a
second interpretation, namely that the root multiplicity of a given root
coincides with the number of acyclic orientations with a unique sink of a
certain graph (depending on the root). Finally, using the combinatorics of
Lyndon words we construct a basis for the root spaces corresponding to these
roots and determine the Hilbert series in the case when all simple roots are
imaginary. As an application we give a Lie theoretic proof of Stanley's
reciprocity theorem of chromatic polynomials.


title:
Exceptional field theories, superparticles in an enlarged 11D superspace
  and higher spin theories

abstract:
  Recently proposed exceptional field theories (EFTs) making manifest the
duality $E_{n(n)}$ symmetry, first observed as nonlinearly realized symmetries
of the maximal $d=3,4,...,9$ supergravity ($n=11-d$) and containing 11D and
type IIB supergravity as sectors, were formulated in enlarged spacetimes. In
the case of $E_{7(7)}$ EFT such an enlarged spacetime can be identified with
the bosonic body of the $d=4$ central charge superspace $\Sigma^{(60|32)}$, the
${\cal N}=8$ $d=4$ superspace completed by 56 additional bosonic coordinates
associated to central charges of the maximal $d=4$ supersymmetry algebra.
  In this paper we show how the hypothesis on the relation of all the known
$E_{n(n)}$ EFTs, including $n=8$, with supersymmetry leads to the conjecture on
existence of 11D exceptional field theory living in 11D tensorial central
charge superspace $\Sigma^{(528|32)}$ and underlying all the $E_{n(n)}$ EFTs
with $n=2,...,8$, and probably the double field theory (DFT). We conjecture the
possible form of the section conditions of such an 11D EFT and show that quite
generic solutions of these can be generated by superparticle models the ground
states of which preserve from one half to all but one supersymmetry. The
properties of these superparticle models are briefly discussed. We argue that,
upon quantization, their quantum states should describe free massless
non-conformal higher spin fields in D=11.
  We also discuss some relevant representations of the M-theory superalgebra
which, in the present context, describes supersymmetry of the 11D EFT.


title:
Quantum Monte-Carlo study of the Bose polaron problem in a
  one-dimensional gas with contact interactions

abstract:
  We present a theoretical study based upon quantum Monte Carlo methods of the
Bose polaron in one-dimensional systems with contact interactions. In this
instance of the problem of a single impurity immersed in a quantum bath, the
medium is a Lieb-Liniger gas of bosons ranging from the weakly interacting to
the Tonks-Girardeau regime, whereas the impurity is coupled to the bath via a
different contact potential producing both repulsive and attractive
interactions. Both the case of a mobile impurity, having the same mass as the
particles in the medium, and of a static impurity with infinite mass are
considered. We make use of exact numerical techniques that allow us to
calculate the ground-state energy of the impurity, its effective mass as well
as the contact parameter between the impurity and the bath. These quantities
are investigated as a function of the strength of interactions between the
impurity and the bath and within the bath. In particular, we find that the
effective mass rapidly increases to very large values when the impurity gets
strongly coupled to an otherwise weakly repulsive bath. This heavy impurity
hardly moves within the medium, thereby realizing the "self-localization"
regime of the Landau-Pekar polaron. Furthermore, we compare our results with
predictions of perturbation theory valid for weak interactions and with exact
solutions available when the bosons in the medium behave as impenetrable
particles.


title: Stereo image de-fencing using smartphones

abstract:
  Conventional approaches to image de-fencing have limited themselves to using
only image data in adjacent frames of the captured video of an approximately
static scene. In this work, we present a method to harness disparity using a
stereo pair of fenced images in order to detect fence pixels. Tourists and
amateur photographers commonly carry smartphones/phablets which can be used to
capture a short video sequence of the fenced scene. We model the formation of
the occluded frames in the captured video. Furthermore, we propose an
optimization framework to estimate the de-fenced image using the total
variation prior to regularize the ill-posed problem.


title: A coordinate-independent version of Hoppensteadt's convergence theorem

abstract:
  The classical theorems about singular perturbation reduction (due to Tikhonov
and Fenichel) are concerned with convergence on a compact time interval (in
slow time) as a small parameter approaches zero. For unbounded time intervals
Hoppensteadt gave a convergence theorem, but his criteria are generally not
easy to apply to concrete given systems. We state and prove a convergence
result for autonomous systems on unbounded time intervals which relies on
criteria that are relatively easy to verify, in particular for the case of a
one-dimensional slow manifold. As for applications, we discuss several reaction
equations from biochemistry.