title:
Serendipitous discovery of a massive cD galaxy at z=1.096: Implications
  for the early formation and late evolution of cD galaxies

abstract:
  We have made a serendipitous discovery of a massive cD galaxy at z=1.096 in a
candidate rich cluster in the HUDF area of GOODS-South. This brightest cluster
galaxy is the most distant cD galaxy confirmed to date. Ultra-deep HST/WFC3
images reveal an extended envelope starting from ~10 kpc and reaching ~70 kpc
in radius along the semi-major axis. The spectral energy distributions indicate
that both its inner component and outer envelope are composed of an old,
passively-evolving stellar population. The cD galaxy lies on the same mass-size
relation as the bulk of quiescent galaxies at similar redshifts. The cD galaxy
has a higher stellar mass surface density but a similar velocity dispersion to
those of more-massive, nearby cDs. If the cD galaxy is one of the progenitors
of today's more massive cDs, its size and stellar mass have had to increase on
average by factors of $3.4\pm1.1$ and $3.3\pm1.3$ over the past ~8 Gyrs,
respectively. Such increases in size and stellar mass without being accompanied
by significant increases in velocity dispersion are consistent with
evolutionary scenarios driven by both major and minor dry mergers. If such cD
envelopes originate from dry mergers, our discovery of even one example proves
that some BCGs entered the dry merger phase at epochs earlier than z=1. Our
data match theoretical models which predict that the continuance of dry mergers
at z<1 can result in structures similar to those of massive cD galaxies seen
today. Moreover, our discovery is a surprise given that the extreme depth of
the HUDF is essential to reveal such an extended cD envelope at z>1 and, yet,
the HUDF covers only a minuscule region of sky. Adding that cDs are rare, Our
serendipitous discovery hints that such cDs may be more common than expected.
[Abridged]


title: Cubature on Wiener space: pathwise convergence

abstract:
  Cubature on Wiener space [Lyons, T.; Victoir, N.; Proc. R. Soc. Lond. A 8
January 2004 vol. 460 no. 2041 169-198] provides a powerful alternative to
Monte Carlo simulation for the integration of certain functionals on Wiener
space. More specifically, and in the language of mathematical finance, cubature
allows for fast computation of European option prices in generic diffusion
models.
  We give a random walk interpretation of cubature and similar (e.g. the
Ninomiya--Victoir) weak approximation schemes. By using rough path analysis, we
are able to establish weak convergence for general path-dependent option
prices.


title: Robust Joint Precoder and Equalizer Design in MIMO Communication Systems

abstract:
  We address joint design of robust precoder and equalizer in a MIMO
communication system using the minimization of weighted sum of mean square
errors. In addition to imperfect knowledge of channel state information, we
also account for inaccurate awareness of interference plus noise covariance
matrix and power shaping matrix. We follow the worst-case model for imperfect
knowledge of these matrices. First, we derive the worst-case values of these
matrices. Then, we transform the joint precoder and equalizer optimization
problem into a convex scalar optimization problem. Further, the solution to
this problem will be simplified to a depressed quartic equation, the
closed-form expressions for roots of which are known. Finally, we propose an
iterative algorithm to obtain the worst-case robust transceivers.


title: Thermodynamics of Strongly Correlated One-Dimensional Bose Gases

abstract:
  We investigate the thermodynamics of one-dimensional Bose gases in the
strongly correlated regime. To this end, we prepare ensembles of independent 1D
Bose gases in a two-dimensional optical lattice and perform high-resolution in
situ imaging of the column-integrated density distribution. Using an inverse
Abel transformation we derive effective one-dimensional line-density profiles
and compare them to exact theoretical models. The high resolution allows for a
direct thermometry of the trapped ensembles. The knowledge about the
temperature enables us to extract thermodynamic equations of state such as the
phase-space density, the entropy per particle and the local pair correlation
function.


title:
Efficient Computation of Representative Sets with Applications in
  Parameterized and Exact Algorithms

abstract:
  We give two algorithms computing representative families of linear and
uniform matroids and demonstrate how to use representative families for
designing single-exponential parameterized and exact exponential time
algorithms. The applications of our approach include
  - LONGEST DIRECTED CYCLE
  - MINIMUM EQUIVALENT GRAPH (MEG)
  - Algorithms on graphs of bounded treewidth
  -k-PATH, k-TREE, and more generally, k-SUBGRAPH ISOMORPHISM, where the
k-vertex pattern graph is of constant treewidth.


title:
On the Optimality of Linear Precoding for Secrecy in the MIMO Broadcast
  Channel

abstract:
  We study the optimality of linear precoding for the two-receiver
multiple-input multiple-output (MIMO) Gaussian broadcast channel (BC) with
confidential messages. Secret dirty-paper coding (SDPC) is optimal under an
input covariance constraint, but there is no computable secrecy capacity
expression for the general MIMO case under an average power constraint. In
principle, for this case, the secrecy capacity region could be found through an
exhaustive search over the set of all possible matrix power constraints.
Clearly, this search, coupled with the complexity of dirty-paper encoding and
decoding, motivates the consideration of low complexity linear precoding as an
alternative. We prove that for a two-user MIMO Gaussian BC under an input
covariance constraint, linear precoding is optimal and achieves the same
secrecy rate region as S-DPC if the input covariance constraint satisfies a
specific condition, and we characterize the corresponding optimal linear
precoders. We then use this result to derive a closed-form sub-optimal
algorithm based on linear precoding for an average power constraint. Numerical
results indicate that the secrecy rate region achieved by this algorithm is
close to that obtained by the optimal S-DPC approach with a search over all
suitable input covariance matrices.


title:
Time-resolved Analysis of Fermi GRBs with Fast and Slow-Cooled
  Synchrotron Photon Models

abstract:
  Time-resolved spectroscopy is performed on eight bright, long gamma-ray
bursts (GRBs) dominated by single emission pulses that were observed with the
{\it Fermi Gamma-ray Space Telescope}. Fitting the prompt radiation of GRBs by
empirical spectral forms such as the Band function leads to ambiguous
conclusions about the physical model for the prompt radiation. Moreover, the
Band function is often inadequate to fit the data. The GRB spectrum is
therefore modeled with two emission components consisting of optically thin
nonthermal synchrotron radiation from relativistic electrons and, when
significant, thermal emission from a jet photosphere, which is represented by a
blackbody spectrum. To produce an acceptable fit, the addition of a blackbody
component is required in 5 out of the 8 cases. We also find that the low-energy
spectral index \alpha is consistent with a synchrotron component with \alpha =
-0.81\pm 0.1. This value lies between the limiting values of \alpha = -2/3 and
\alpha = -3/2 for electrons in the slow and fast-cooling regimes, respectively,
suggesting ongoing acceleration at the emission site. The blackbody component
can be more significant when using a physical synchrotron model instead of the
Band function, illustrating that the Band function does not serve as a good
proxy for a nonthermal synchrotron emission component. The temperature and
characteristic emission-region size of the blackbody component are found to,
respectively, decrease and increase as power laws with time during the prompt
phase. In addition, we find that the blackbody and nonthermal components have
separate temporal behaviors.


title:
Effect of annealing on the superconducting properties of a-Nb(x)Si(1-x)
  thin films

abstract:
  a-Nb(x)Si(1-x) thin films with thicknesses down to 25 {\AA} have been
structurally characterized by TEM (Transmission Electron Microscopy)
measurements. As-deposited or annealed films are shown to be continuous and
homogeneous in composition and thickness, up to an annealing temperature of
500{\deg}C. We have carried out low temperature transport measurements on these
films close to the superconductor-to-insulator transition (SIT), and shown a
qualitative difference between the effect of annealing or composition, and a
reduction of the film thickness on the superconducting properties of a-NbSi.
These results question the pertinence of the sheet resistance R_square as the
relevant parameter to describe the SIT.


title: Spacetime Transformations from a Uniformly Accelerated Frame

abstract:
  We use Generalized Fermi-Walker transport to construct a one-parameter family
of inertial frames which are instantaneously comoving to a uniformly
accelerated observer. We explain the connection between our approach and that
of Mashhoon. We show that our solutions of uniformly accelerated motion have
constant acceleration in the comoving frame. Assuming the Weak Hypothesis of
Locality, we obtain local spacetime transformations from a uniformly
accelerated frame $K'$ to an inertial frame $K$. The spacetime transformations
between two uniformly accelerated frames with the same acceleration are
Lorentz. We compute the metric at an arbitrary point of a uniformly accelerated
frame.


title:
Systematic Scale-Setting to All Orders: The Principle of Maximum
  Conformality and Commensurate Scale Relations

abstract:
  We present in detail a new systematic method which can be used to
automatically eliminate the renormalization scheme and scale ambiguities in
perturbative QCD predictions at all orders. We show that all of the
nonconformal \beta-dependent terms in a QCD perturbative series can be readily
identified by generalizing the conventional renormalization schemes based on
dimensional regularization. We then demonstrate that the nonconformal series of
pQCD at any order can be resummed systematically into the scale of the QCD
coupling in a unique and unambiguous way due to a special degeneracy of the
\beta-terms in the series. The resummation follows from the principal of
maximum conformality (PMC) and assigns a unique scale for the running coupling
at each perturbative order. The final result is independent of the initial
choices of renormalization scheme and scale, in accordance with the principles
of the renormalization group, and thus eliminates an unnecessary source of
systematic error in physical predictions. We exhibit several examples known to
order \alpha_s^4; i.e. i) the electron-positron annihilation into hadrons, ii)
the tau-lepton decay to hadrons, iii) the Bjorken and Gross-Llewellyn Smith
(GLS) sum rules, and iv) the static quark potential. We show that the final
series of the first three cases are all given in terms of the anomalous
dimension of the gluon field, in accordance with conformality, and with all
non-conformal properties encoded in the running coupling. The final expressions
for the Bjorken and GLS sum rules directly lead to the generalized Crewther
relations, exposing another relevant feature of conformality. The static quark
potential shows that PMC scale setting in the Abelian limit is to all orders
consistent with QED scale setting. Finally, we demonstrate that the method
applies to any renormalization scheme and [...]


title: Lifting Automorphisms of Quotients by Central Subgroups

abstract:
  Given a finitely presented group $G$, we wish to explore the conditions under
which automorphisms of quotients $G/N$ can be lifted to automorphisms of $G$.
We discover that in the case where $N$ is a central subgroup of $G$, the
question of lifting can be reduced to solving a certain matrix equation. We
then use the techniques developed to show that $Inn(G)$ is not characteristic
in $Aut(G)$, where $G$ is a metacyclic group of order $p^n$, $p\neq 2$.


title: PAC Quasi-automatizability of Resolution over Restricted Distributions

abstract:
  We consider principled alternatives to unsupervised learning in data mining
by situating the learning task in the context of the subsequent analysis task.
Specifically, we consider a query-answering (hypothesis-testing) task: In the
combined task, we decide whether an input query formula is satisfied over a
background distribution by using input examples directly, rather than invoking
a two-stage process in which (i) rules over the distribution are learned by an
unsupervised learning algorithm and (ii) a reasoning algorithm decides whether
or not the query formula follows from the learned rules. In a previous work
(2013), we observed that the learning task could satisfy numerous desirable
criteria in this combined context -- effectively matching what could be
achieved by agnostic learning of CNFs from partial information -- that are not
known to be achievable directly. In this work, we show that likewise, there are
reasoning tasks that are achievable in such a combined context that are not
known to be achievable directly (and indeed, have been seriously conjectured to
be impossible, cf. (Alekhnovich and Razborov, 2008)). Namely, we test for a
resolution proof of the query formula of a given size in quasipolynomial time
(that is, "quasi-automatizing" resolution). The learning setting we consider is
a partial-information, restricted-distribution setting that generalizes
learning parities over the uniform distribution from partial information,
another task that is known not to be achievable directly in various models (cf.
(Ben-David and Dichterman, 1998) and (Michael, 2010)).


title:
Speckle Reduction in Polarimetric SAR Imagery with Stochastic Distances
  and Nonlocal Means

abstract:
  This paper presents a technique for reducing speckle in Polarimetric
Synthetic Aperture Radar (PolSAR) imagery using Nonlocal Means and a
statistical test based on stochastic divergences. The main objective is to
select homogeneous pixels in the filtering area through statistical tests
between distributions. This proposal uses the complex Wishart model to describe
PolSAR data, but the technique can be extended to other models. The weights of
the location-variant linear filter are function of the p-values of tests which
verify the hypothesis that two samples come from the same distribution and,
therefore, can be used to compute a local mean. The test stems from the family
of (h-phi) divergences which originated in Information Theory. This novel
technique was compared with the Boxcar, Refined Lee and IDAN filters. Image
quality assessment methods on simulated and real data are employed to validate
the performance of this approach. We show that the proposed filter also
enhances the polarimetric entropy and preserves the scattering information of
the targets.

categories: cs.IT cs.CV cs.GR math.IT stat.AP stat.ML


title:
Patterns In The Coefficients Of Powers Of Polynomials Over A Finite
  Field

abstract:
  We examine the behavior of the coefficients of powers of polynomials over a
finite field of prime order. Extending the work of Allouche-Berthe, 1997, we
study a(n), the number of occurring strings of length n among coefficients of
any power of a polynomial f reduced modulo a prime p. The sequence of line
complexity a(n) is p-regular in the sense of Allouche-Shalit. For f=1+x and
general p, we derive a recursion relation for a(n) then find a new formula for
the generating function for a(n). We use the generating function to compute the
asymptotics of a(n)/n^2 as n approaches infinity, which is an explicitly
computable piecewise quadratic in x with n= [p^m/x] and x is a real number
between 1/p and 1. Analyzing other cases, we form a conjecture about the
generating function for general a(n). We examine the matrix B associated with f
and p used to compute the count of a coefficient, which applies to the theory
of linear cellular automata and fractals. For p=2 and polynomials of small
degree we compute the largest positive eigenvalue, \lambda, of B, related to
the fractal dimension d of the corresponding fractal by d= \log_2(\lambda). We
find proofs and make a number of conjectures for some bounds on \lambda, and
upper bounds on its degree.


title: When Distributed Computation is Communication Expensive

abstract:
  We consider a number of fundamental statistical and graph problems in the
message-passing model, where we have $k$ machines (sites), each holding a piece
of data, and the machines want to jointly solve a problem defined on the union
of the $k$ data sets. The communication is point-to-point, and the goal is to
minimize the total communication among the $k$ machines. This model captures
all point-to-point distributed computational models with respect to minimizing
communication costs. Our analysis shows that exact computation of many
statistical and graph problems in this distributed setting requires a
prohibitively large amount of communication, and often one cannot improve upon
the communication of the simple protocol in which all machines send their data
to a centralized server. Thus, in order to obtain protocols that are
communication-efficient, one has to allow approximation, or investigate the
distribution or layout of the data sets.


title:
Two-Stage Plans for Estimating a Threshold Value of a Regression
  Function

abstract:
  This study investigates two-stage plans based on nonparametric procedures for
estimating an inverse regression function at a given point. Specifically,
isotonic regression is used at stage one to obtain an initial estimate followed
by another round of isotonic regression in the vicinity of this estimate at
stage two. It is shown that such two stage plans accelerate the convergence
rate of one-stage procedures and are superior to existing two-stage procedures
that use local parametric approximations at stage two when the available budget
is moderate and/or the regression function is 'ill-behaved'. Both Wald and
Likelihood Ratio type confidence intervals for the threshold value of interest
are investigated and the latter are recommended in applications due to their
simplicity and robustness. The developed plans are illustrated through a
comprehensive simulation study and an application to car fuel efficiency data.


title: Drag reduction by a solid wall emulating spanwise oscillations. Part 1

abstract:
  A new idea for turbulent skin-friction reduction is proposed, wherein the
shape of the solid wall is designed to create the spanwise pressure gradient
acting similarly to the well-known method of drag reduction by in-plane
spanwise wall motion. Estimates based on the assumption of similarity with drag
reduction effect of in-plane wall motion suggest that drag reduction of about
2.4% can be achieved in the flow past a wavy wall, with the crests forming an
angle of about 38 degrees with the main flow direction, and the wave period in
the main flow direction equal to about 1500 wall units. The required height of
the wall waves have to be adjusted to achieve the same intensity of the
spanwise motion as that created by an in-plane moving wall of the same
wavelength and with peak wall velocity equal to 2 wall units. Further research
is being conducted in order to determine this height. Suggestions are made for
further research on confirming the feasibility of the proposed method and on
optimising the wall shape.


title: A 4D Composite Higgs Model: Testing its Scalar Sector at the LHC

abstract:
  We explain the current Large Hadron Collider (LHC) data pointing to the
discovery of a neutral Higgs boson in the context of a 4-Dimensional Composite
Higgs Model (4DCHM). The full particle spectrum of this scenario is derived
without any approximation and implemented in automated computational tools to
enable fast phenomenological investigation. Several parameter configurations
compliant with experimental constraints are presented and discussed. A $\chi^2$
fit to the LHC data quantifying the consistency of the 4DCHM as a whole with
experimental evidence is finally performed.


title: Trait substitution trees on two time scales analysis

abstract:
  In this paper we consider two continuous-mass population models as analogues
of logistic branching random walks, one is supported on a finite trait space
and the other one is supported on an infinite trait space. For the first model
with nearest-neighbor competition and migration, we justify a well-described
evolutionary path to the short-term equilibrium on a slow migration time scale.
For the second one with an additional evolutionary mechanism-mutation, a jump
process-trait substitution tree model is established under a combination of
rare mutation and slow migration limits. The transition rule of the tree highly
depends on the relabelled trait sequence determined by the fitness landscape.
The novelty of our model is that each trait, which may nearly die out on the
migration time scale, has a chance to recover and further to be stabilized on
the mutation time scale because of a change in the fitness landscape due to a
newly entering mutant.


title:
Uniform Distribution of Prime Powers and sets of Recurrence and van der
  Corput sets in Z^k

abstract:
  We establish new results on sets of recurrence and van der Corput sets in Z^k
which refine and unify some of the previous results obtained by Sarkozy,
Furstenberg, Kamae and Mendes France, and Bergelson and Lesigne. The proofs
utilize a general equidistribution result involving prime powers which is of
independent interest.


title: Easy and hard functions for the Boolean hidden shift problem

abstract:
  We study the quantum query complexity of the Boolean hidden shift problem.
Given oracle access to f(x+s) for a known Boolean function f, the task is to
determine the n-bit string s. The quantum query complexity of this problem
depends strongly on f. We demonstrate that the easiest instances of this
problem correspond to bent functions, in the sense that an exact one-query
algorithm exists if and only if the function is bent. We partially characterize
the hardest instances, which include delta functions. Moreover, we show that
the problem is easy for random functions, since two queries suffice. Our
algorithm for random functions is based on performing the pretty good
measurement on several copies of a certain state; its analysis relies on the
Fourier transform. We also use this approach to improve the quantum rejection
sampling approach to the Boolean hidden shift problem.


title:
The Lick AGN Monitoring Project 2011: Fe II Reverberation from the Outer
  Broad-Line Region

abstract:
  The prominent broad Fe II emission blends in the spectra of active galactic
nuclei have been shown to vary in response to continuum variations, but past
attempts to measure the reverberation lag time of the optical Fe II lines have
met with only limited success. Here we report the detection of Fe II
reverberation in two Seyfert 1 galaxies, NGC 4593 and Mrk 1511, based on data
from a program carried out at Lick Observatory in Spring 2011. Light curves for
emission lines including H-beta and Fe II were measured by applying a fitting
routine to decompose the spectra into several continuum and emission-line
components, and we use cross-correlation techniques to determine the
reverberation lags of the emission lines relative to V-band light curves. In
both cases the measured lag (t_cen) of Fe II is longer than that of H-beta,
although the inferred lags are somewhat sensitive to the choice of Fe II
template used in the fit. For spectral decompositions done using the Fe II
template of Veron-Cetty et al. (2004), we find t_cen(Fe II)/t_cen(H-beta) =
1.9+-0.6 in NGC 4593 and 1.5+-0.3 in Mrk 1511. The detection of highly
correlated variations between Fe II and continuum emission demonstrates that
the Fe II emission in these galaxies originates in photoionized gas, located
predominantly in the outer portion of the broad-line region.


title:
A connection between radio state changing and glitch activity in PSR
  J0742-2822

abstract:
  PSR J0742-2822 exhibits two distinct emission states that are identified by
discrete changes in the observed pulse profile. These changes have previously
been shown to correlate with changes in the derivative of the pulse frequency.
In this paper, we use observations with the Parkes radio telescope at a centre
frequency of 1369 and 3100 MHz to produce high phase resolution polarisation
profiles for the two modes and perform a detailed study of the correlation
between observed pulse shape and spin-down rate. We find no correlation for at
least 200 days prior to a glitch in the pulsar at MJD 55022, following which
the correlation becomes strong. This suggests a link between the emission state
switching phenomenon and glitch events. We discuss the possibility that
emission state switching is driven by the interaction between the magnetosphere
and the interior of the neutron star.


title:
On the Action of the Symmetric Group on the Cohomology of Groups Related
  to (Virtual) Braids

abstract:
  In this paper we consider the cohomology of four groups related to the
virtual braids of [Kauffman] and [Goussarov-Polyak-Viro], namely the pure and
non-pure virtual braid groups (PvB_n and vB_n, respectively), and the pure and
non-pure flat braid groups (PfB_n and fB_n, respectively). The cohomologies of
PvB_n and PfB_n admit an action of the symmetric group S_n. We give a
description of the cohomology modules H^i(PvB_n,Q) and H^i(PfB_n,Q) as sums of
S_n-modules induced from certain one-dimensional representations of specific
subgroups of S_n. This in particular allows us to conclude that H^i(PvB_n,Q)
and H^i(PfB_n,Q) are uniformly representation stable, in the sense of
[Church-Farb]. We also give plethystic formulas for the Frobenius
characteristics of these S_n-modules. We then derive a number of constraints on
which S_n irreducibles may appear in H^i(PvB_n,Q) and H^i(PfB_n,Q). In
particular, we show that the multiplicity of the alternating representation in
H^i(PvB_n,Q) and H^i(PfB_n,Q) is identical, and moreover is nil for
sufficiently large $n$. We use this to recover the (previously known) fact that
the multiplicity of the alternating representation in H^i(PB_n,Q) is nil (here
PB_n is the ordinary pure braid group). We also give an explicit formula for
H^i(vB_n,Q) and show that H^i(fB_n,Q)=0. Finally, we give Hilbert series for
the character of the action of S_n on H^i(PvB_n,Q) and H^i(PfB_n,Q). An
extension of the standard `Koszul formula' for the graded dimension of Koszul
algebras to graded characters of Koszul algebras then gives Hilbert series for
the graded characters of the respective quadratic dual algebras.


title:
Constraints on the shape of the Milky Way dark matter halo from the
  Sagittarius stream

abstract:
  We propose a new model for the dark matter halo of the Milky Way that fits
the properties of the stellar stream associated with the Sagittarius dwarf
galaxy. Our dark halo is oblate with q_z = 0.9 for r < 10 kpc, and can be made
to follow the Law & Majewski model at larger radii. However, we find that the
dynamical perturbations induced by the Large Magellanic Cloud on the orbit of
Sgr cannot be neglected when modeling its streams. When taken into account,
this leads us to constrain the Galaxy's outer halo shape to have minor-to-major
axis ratio (c/a)_\Phi = 0.8 and intermediate-to-major axis ratio (b/a)_\Phi =
0.9, in good agreement with cosmological expectations.


title: Propagation of the Gravo-Magneto Disc Instability

abstract:
  Discs that contain dead zones are subject to the Gravo-Magneto (GM)
instability that arises when the turbulence shifts from gravitational to
magnetic. We have previously described this instability through a local
analysis at some radius in the disc in terms of a limit cycle. A disc may be
locally unstable over a radial interval. In this paper, we consider how the
local instability model can describe global disc outbursts. The outburst is
triggered near the middle of the range of locally unstable radii. The sudden
increase in turbulence within high surface density material causes a snow
plough of density that propagates both inwards and outwards. All radii inside
of the trigger radius become unstable, as well as locally unstable radii
outside the trigger radius. In addition, a locally stable region outside of the
trigger radius may also become unstable as the gravitational instability is
enhanced by the snow plough. For the circumstellar disc model we consider, we
find that a quarter of the disc mass is accreted on to the central object
during the outburst. The radius out to which the disc is globally unstable is
twice that for which it is locally unstable.


title: Construction of Self-dual Codes over $F_p+vF_p$

abstract:
  In this paper, we determine all self-dual codes over $F_p+vF_p$ ($v^2=v$) in
terms of self-dual codes over the finite field $F_p$ and give an explicit
construction for self-dual codes over $F_p+vF_p$, where $p$ is a prime.


title:
Precessing Warped Be Disk Triggering the Giant Outbursts in 2009 and
  2011 in A 0535+262/V725 Tau

abstract:
  We carried out optical high-dispersion spectroscopic monitoring of the Be
disk in a Be/X-ray binary A 0535+262/V725 Tau from 2009 to 2012, covering two
giant outbursts and several normal outbursts. This monitoring was performed in
order to investigate variabilities of the Be disk due to the interaction with
the neutron star in recent X-ray active phase from 2008 to 2011. Such
variabilities give a clue to uncleared detailed mechanism for very bright X-ray
outbursts, which are unique to some Be/X-ray binaries with relatively wide and
eccentric orbit. In the previous letter (Moritani et al. 2011), a brief
overview of line profile variabilities around the 2009 giant outburst was given
and the possibility of a warped Be disk was discussed. In this paper, a full
analysis of the Halpha line profiles as well as other line profiles is carried
out. A bright blue component, or blue "shoulder", showing up after periastron
indicates the presence of a dense gas stream toward the neutron star, which is
associated with observed outbursts. We re-analyze the Halpha line profiles
before 2009 (down to 2005) in order to investigate the variability of the the
disk structure in the innermost region, which seems to have detached from the
Be star surface by 2008. A redshifted enhanced component is remarkable in all
emission lines observed around the 2009 giant outburst, occasionally forming a
triple peak. These features indicate that the Be disk was warped in X-ray
active phase. We estimate the position of the warped region from fitting the
radial velocity of the redshifted enhanced component of Halpha, and find that
it was very close to the periastron when two giant outbursts in 2009 and 2011
and a bright normal outburst in 2010 March occurred. These facts strongly
suggest that the warped Be disk triggered these giant outbursts.


title: Conformal Higgs model: Gauge fields can produce a 125GeV resonance

abstract:
  Recent cosmological observations and compatible theory offer an understanding
of long-mysterious dark matter and dark energy. The postulate of universal
conformal local Weyl scaling symmetry, without dark matter, modifies action
integrals for both Einstein-Hilbert gravitation and the Higgs scalar field by
nonclassical gravitational terms. Conformal theory accounts both for observed
excessive external galactic orbital velocities and for accelerating cosmic
expansion. SU(2) symmetry-breaking is retained but dark energy is implied
rather than nonzero Higgs particle mass. These results are compatible with
existence of a massive neutral particle or resonance $W_2$ at 125GeV, described
as composite scalar $g_{\mu\nu}W_-^\mu W_+^\nu$ and $g_{\mu\nu}Z^{\mu*}Z^\nu$
interacting strongly via quark exchange. Decay modes would be consistent with
those observed at LHC. Higgs scalar field $\Phi$ is dressed by the $W_2$ field
to produce Lagrangian term $\lambda(\Phi^\dagger\Phi)^2$.


title: Generalized Public Key Transformations with Side Information

abstract:
  This paper presents results on generalized public key cryptography with
exponentials modulo primes and composite numbers where the mapping is not
one-to-one and the uniqueness is achieved by additional side information. Such
transformations may be used for oblivious transfer and generate events of
specific probabilities.


title: A Health Monitoring System for Elder and Sick Persons

abstract:
  This paper discusses a vision based health monitoring system which would be
very easy in use and deployment. Elder and sick people who are not able to talk
or walk they are dependent on other human beings for their daily needs and need
continuous monitoring. The developed system provides facility to the sick or
elder person to describe his or her need to their caretaker in lingual
description by showing particular hand gesture with the developed system. This
system uses fingertip detection technique for gesture extraction and artificial
neural network for gesture classification and recognition. The system is able
to work in different light conditions and can be connected to different devices
to announce users need on a distant location.


title:
A variant of H\"ormander's $L^2$ theorem for Dirac operator in Clifford
  analysis

abstract:
  In this paper, we give the H\"ormander's $L^2$ theorem for Dirac operator
over an open subset $\Omega\in\R^{n+1}$ with Clifford algebra. Some sufficient
condition on the existence of the weak solutions for Dirac operator has been
found in the sense of Clifford analysis. In particular, if $\Omega$ is bounded,
then we prove that for any $f$ in $L^2$ space with value in Clifford algebra,
there exists a weak solution of Dirac operator such that $$\bar{D}u=f$$ with
$u$ in the $L^2$ space as well. The method is based on H\"ormander's $L^2$
existence theorem in complex analysis and the $L^2$ weighted space is utilised.


title: Graph estimation with joint additive models

abstract:
  In recent years, there has been considerable interest in estimating
conditional independence graphs in the high-dimensional setting. Most prior
work has assumed that the variables are multivariate Gaussian, or that the
conditional means of the variables are linear. Unfortunately, if these
assumptions are violated, then the resulting conditional independence estimates
can be inaccurate. We present a semi-parametric method, SpaCE JAM, which allows
the conditional means of the features to take on an arbitrary additive form. We
present an efficient algorithm for its computation, and prove that our
estimator is consistent. We also extend our method to estimation of directed
graphs with known causal ordering. Using simulated data, we show that SpaCE JAM
enjoys superior performance to existing methods when there are non-linear
relationships among the features, and is comparable to methods that assume
multivariate normality when the conditional means are linear. We illustrate our
method on a cell-signaling data set.


title: Invariants of Links in Thickened Surfaces

abstract:
  A group invariant for links in thickened closed orientable surfaces is
studied. Associated polynomial invariants are defined. The group detects
nontriviality of a virtual link and determines its virtual genus.


title: Reducing Systematic Error in Cluster Scale Weak Lensing

abstract:
  Weak lensing provides an important route toward collecting samples of
clusters of galaxies selected by mass. Subtle systematic errors in image
reduction can compromise the power of this technique. We use the B-mode signal
to quantify this systematic error and to test methods for reducing this error.
We show that two procedures are efficient in suppressing systematic error in
the B-mode: (1) refinement of the mosaic CCD warping procedure to conform to
absolute celestial coordinates and (2) truncation of the smoothing procedure on
a scale of 10$^{\prime}$. Application of these procedures reduces the
systematic error to 20% of its original amplitude. We provide an analytic
expression for the distribution of the highest peaks in noise maps that can be
used to estimate the fraction of false peaks in the weak lensing $\kappa$-S/N
maps as a function of the detection threshold. Based on this analysis we select
a threshold S/N = 4.56 for identifying an uncontaminated set of weak lensing
peaks in two test fields covering a total area of $\sim 3$deg$^2$. Taken
together these fields contain seven peaks above the threshold. Among these, six
are probable systems of galaxies and one is a superposition. We confirm the
reliability of these peaks with dense redshift surveys, x-ray and imaging
observations. The systematic error reduction procedures we apply are general
and can be applied to future large-area weak lensing surveys. Our high peak
analysis suggests that with a S/N threshold of 4.5, there should be only 2.7
spurious weak lensing peaks even in an area of 1000 deg$^2$ where we expect
$\sim$ 2000 peaks based on our Subaru fields.


title: DELTACON: A Principled Massive-Graph Similarity Function

abstract:
  How much did a network change since yesterday? How different is the wiring
between Bob's brain (a left-handed male) and Alice's brain (a right-handed
female)? Graph similarity with known node correspondence, i.e. the detection of
changes in the connectivity of graphs, arises in numerous settings. In this
work, we formally state the axioms and desired properties of the graph
similarity functions, and evaluate when state-of-the-art methods fail to detect
crucial connectivity changes in graphs. We propose DeltaCon, a principled,
intuitive, and scalable algorithm that assesses the similarity between two
graphs on the same nodes (e.g. employees of a company, customers of a mobile
carrier). Experiments on various synthetic and real graphs showcase the
advantages of our method over existing similarity measures. Finally, we employ
DeltaCon to real applications: (a) we classify people to groups of high and low
creativity based on their brain connectivity graphs, and (b) do temporal
anomaly detection in the who-emails-whom Enron graph.


title: Personalized PageRank to a Target Node

abstract:
  Personalalized PageRank uses random walks to determine the importance or
authority of nodes in a graph from the point of view of a given source node.
Much past work has considered how to compute personalized PageRank from a given
source node to other nodes. In this work we consider the problem of computing
personalized PageRanks to a given target node from all source nodes. This
problem can be interpreted as finding who supports the target or who is
interested in the target.
  We present an efficient algorithm for computing personalized PageRank to a
given target up to any given accuracy. We give a simple analysis of our
algorithm's running time in both the average case and the parameterized
worst-case. We show that for any graph with $n$ nodes and $m$ edges, if the
target node is randomly chosen and the teleport probability $\alpha$ is given,
the algorithm will compute a result with $\epsilon$ error in time
$O\left(\frac{1}{\alpha \epsilon} \left(\frac{m}{n} + \log(n)\right)\right)$.
This is much faster than the previously proposed method of computing
personalized PageRank separately from every source node, and it is comparable
to the cost of computing personalized PageRank from a single source. We present
results from experiments on the Twitter graph which show that the constant
factors in our running time analysis are small and our algorithm is efficient
in practice.


title: The Variety Generated by A(T) -- Two Counterexamples

abstract:
  We show that V(A(T)) does not have definable principal subcongruences or
bounded Maltsev depth. When the Turing machine T halts, V(A(T)) is an example
of a finitely generated semilattice based (and hence congruence
meet-semidistributive) variety with only finitely many subdirectly irreducible
members, all finite. This is the only known example of a variety with these
properties that does not have definable principal subcongruences or bounded
Maltsev depth.


title:
A dual-isotope rubidium comagnetometer to search for anomalous
  long-range spin-mass (spin-gravity) couplings of the proton

abstract:
  The experimental concept of a search for a long-range coupling between
rubidium (Rb) nuclear spins and the mass of the Earth is described. The
experiment is based on simultaneous measurement of the spin precession
frequencies for overlapping ensembles of Rb-85 and Rb-87 atoms contained within
an evacuated, antirelaxation-coated vapor cell. Rubidium atoms are
spin-polarized in the presence of an applied magnetic field by synchronous
optical pumping with circularly polarized laser light. Spin precession is
probed by measuring optical rotation of far-off-resonant, linearly polarized
laser light. Simultaneous measurement of Rb-85 and Rb-87 spin precession
frequencies enables suppression of magnetic-field-related systematic effects.
The nuclear structure of the Rb isotopes makes the experiment particularly
sensitive to anomalous spin-dependent interactions of the proton. Experimental
sensitivity and a variety of systematic effects are discussed, and initial data
are presented.


title:
Fast Exact Shortest-Path Distance Queries on Large Networks by Pruned
  Landmark Labeling

abstract:
  We propose a new exact method for shortest-path distance queries on
large-scale networks. Our method precomputes distance labels for vertices by
performing a breadth-first search from every vertex. Seemingly too obvious and
too inefficient at first glance, the key ingredient introduced here is pruning
during breadth-first searches. While we can still answer the correct distance
for any pair of vertices from the labels, it surprisingly reduces the search
space and sizes of labels. Moreover, we show that we can perform 32 or 64
breadth-first searches simultaneously exploiting bitwise operations. We
experimentally demonstrate that the combination of these two techniques is
efficient and robust on various kinds of large-scale real-world networks. In
particular, our method can handle social networks and web graphs with hundreds
of millions of edges, which are two orders of magnitude larger than the limits
of previous exact methods, with comparable query time to those of previous
methods.


title: Tracking of Fingertips and Centres of Palm using KINECT

abstract:
  Hand Gesture is a popular way to interact or control machines and it has been
implemented in many applications. The geometry of hand is such that it is hard
to construct in virtual environment and control the joints but the
functionality and DOF encourage researchers to make a hand like instrument.
This paper presents a novel method for fingertips detection and centres of
palms detection distinctly for both hands using MS KINECT in 3D from the input
image. KINECT facilitates us by providing the depth information of foreground
objects. The hands were segmented using the depth vector and centres of palms
were detected using distance transformation on inverse image. This result would
be used to feed the inputs to the robotic hands to emulate human hands
operation.


title:
Numerical study of the stability regions for half-quantum vortices in
  superconducting Sr2RuO4

abstract:
  We numerically solve the coupled Landau-Ginzburg-Maxwell equations for a
model of a spin triplet px + ipy superconductor in which whole or half-quanta
of flux thread through a hole. We recover the pattern of stable and unstable
regions for the half-flux quanta observed in a recent experiment.


title: Product line Development Architectural Model

abstract:
  Products with new features need to be introduced on the market in a rapid
pace and organizations need to speed up their development process. The ordinary
way to develop products, one at a time, is not time efficient enough and is
costly. Reuse has been suggested as a solution, but to achieve effective reuse
within an organization a planned and proactive effort must be used. Product
lines are the most promising technique and it increases productivity and
software quality and decreases time-to-market. This paper describes the
architecture of product line engineering process and also addresses what the
design issues of product line architecture are and how a UML profile looks like
for a product line by referring to the basic aspects of a case study,
CelsiusTech in its Naval Product Line, SS2000.


title: On a state model for the SO(2n) Kauffman polynomial

abstract:
  F. Jaeger presented the two-variable Kauffman polynomial of an unoriented
link L as a weighted sum of HOMFLY-PT polynomials of oriented links associated
with L. Murakami, Ohtsuki and Yamada (MOY) used planar graphs and a recursive
evaluation of these graphs to construct a state model for the sl(n)-link
invariant (a one-variable specialization of the HOMFLY-PT polynomial). We apply
the MOY framework to Jaeger's work, and construct a state summation model for
the SO(2n) Kauffman polynomial.


title:
Multi-Branch MMSE Decision Feedback Detection Algorithms with Error
  Propagation Mitigation for Multi-Antenna Systems

abstract:
  In this work we propose novel decision feedback (DF) detection algorithms
with error propagation mitigation capabilities for multi-input multi-output
(MIMO) spatial multiplexing systems based on multiple processing branches. The
novel strategies for detection exploit different patterns, orderings and
constraints for the design of the feedforward and feedback filters. We present
constrained minimum mean-squared error (MMSE) filters designed with constraints
on the shape and magnitude of the feedback filters for the multi-branch MIMO
receivers and show that the proposed MMSE design does not require a significant
additional complexity over the single-branch MMSE design. The proposed
multi-branch MMSE DF detectors are compared with several existing detectors and
are shown to achieve a performance close to the optimal maximum likelihood
detector while requiring significantly lower complexity.


title:
The Baker-Campbell-Hausdorff formula and the Zassenhaus formula in
  synthetic differential geometry

abstract:
  After the torch of Anders Kock [Taylor series calculus for ring objects of
line type, Journal of Pure and Applied Algebra, 12 (1978), 271-293], we will
establish the Baker-Campbell-Hausdorff formula as well as the Zassenhaus
formula in the theory of Lie groups.


title:
Universal density scaling of disorder-limited low-temperature
  conductivity in high-mobility two-dimensional systems

abstract:
  We theoretically consider the carrier density dependence of low-temperature
electrical conductivity in high-quality and low-disorder two-dimensional (2D)
`metallic' electronic systems such as 2D GaAs electron or hole quantum wells or
gated graphene. Taking into account resistive scattering by Coulomb disorder
arising from quenched random charged impurities in the environment, we show
that the 2D conductivity \sigma(n) varies as \sigma ~ n^{\beta(n)} as a
function of the 2D carrier density n where the exponent \beta(n) is a smooth,
but non-monotonic, function of density with possible nontrivial extrema. In
particular, the density scaling exponent \beta(n) depends qualitatively on
whether the Coulomb disorder arises primarily from remote or background charged
impurities or short-range disorder, and can, in principle, be used to
characterize the nature of the dominant background disorder. A specific
important prediction of the theory is that for resistive scattering by remote
charged impurities, the exponent \beta can reach a value as large as 2.7 for
k_F d ~ 1, where k_F ~\sqrt{n} is the 2D Fermi wave vector and d is the
separation of the remote impurities from the 2D layer. Such an exponent \beta
(>5/2) is surprising because unscreened Coulomb scattering by remote impurities
gives a limiting theoretical scaling exponent of \beta = 5/2, and naively one
would expect \beta(n) \le 5/2 for all densities since unscreened Coulomb
scattering should nominally be the situation bounding the resistive scattering
from above. We find numerically and show theoretically that the maximum value
of \alpha (\beta), the mobility (conductivity) exponent, for 2D semiconductor
quantum wells is around 1.7 (2.7) for all values of d (and for both electrons
and holes) with the maximum \alpha occurring around k_F d ~ 1. We discuss
experimental scenarios for the verification of our theory.


title:
Improved Carrier Mobility in Few-Layer MoS2 Field-Effect Transistors
  with Ionic-Liquid Gating

abstract:
  We report the fabrication of ionic liquid (IL) gated field-effect transistors
(FETs) consisting of bilayer and few-layer MoS2. Our transport measurements
indicate that the electron mobility about 60 cm2V-1s-1 at 250 K in ionic liquid
gated devices exceeds significantly that of comparable back-gated devices.
IL-FETs display a mobility increase from about 100 cm2V-1s-1 at 180 K to about
220 cm2V-1s-1 at 77 K in good agreement with the true channel mobility
determined from four-terminal measurements, ambipolar behavior with a high
ON/OFF ratio >107 (104) for electrons (holes), and a near ideal sub-threshold
swing of about 50 mV/dec at 250 K. We attribute the observed performance
enhancement, specifically the increased carrier mobility that is limited by
phonons, to the reduction of the Schottky barrier at the source and drain
electrode by band bending caused by the ultrathin ionic-liquid dielectric
layer.


title: $J/\psi$ production associated with a $W$-boson at the $7 TeV$ LHC

abstract:
  We calculate the complete next-to-leading order (NLO) QCD corrections to the
$J/\psi +W$ associated production within the factorization formalism of
nonrelativistic QCD at the $7 TeV$ LHC. We provide the numerical results for
the leading-order (LO), NLO QCD corrected differential cross sections of the
$J/\psi$ transverse momentum by adopting the event selection criteria requested
by the ATLAS experiment. We find that the differential cross section at the LO
is significantly enhanced by the NLO QCD corrections.


title:
Still water: dead zones and collimated ejecta from the impact of
  granular jets

abstract:
  When a dense granular jet hits a target, it forms a large dead zone and
ejects a highly collimated conical sheet with a well-defined opening angle.
Using experiments, simulations, and continuum modeling, we find that this
opening angle is insensitive to the precise target shape and the dissipation
mechanisms in the flow. We show that this surprising insensitivity arises
because dense granular jet impact, though highly dissipative, is nonetheless
controlled by the limit of perfect fluid flow.


title: Low-Rank Matrix and Tensor Completion via Adaptive Sampling

abstract:
  We study low rank matrix and tensor completion and propose novel algorithms
that employ adaptive sampling schemes to obtain strong performance guarantees.
Our algorithms exploit adaptivity to identify entries that are highly
informative for learning the column space of the matrix (tensor) and
consequently, our results hold even when the row space is highly coherent, in
contrast with previous analyses. In the absence of noise, we show that one can
exactly recover a $n \times n$ matrix of rank $r$ from merely $\Omega(n
r^{3/2}\log(r))$ matrix entries. We also show that one can recover an order $T$
tensor using $\Omega(n r^{T-1/2}T^2 \log(r))$ entries. For noisy recovery, our
algorithm consistently estimates a low rank matrix corrupted with noise using
$\Omega(n r^{3/2} \textrm{polylog}(n))$ entries. We complement our study with
simulations that verify our theory and demonstrate the scalability of our
algorithms.


title:
To be or not to be social: Foraging associations of free-ranging dogs in
  an urban ecosystem

abstract:
  Canids display a wide diversity of social systems, from solitary to pairs to
packs, and hence they have been extensively used as model systems to understand
social dynamics in natural systems. Among canids, the dog can show various
levels of social organization due to the influence of humans on their lives.
Though the dog is known as man's best friend and has been studied extensively
as a pet, studies on the natural history, ecology and behaviour of dogs in a
natural habitat are rare. Here we report results of an extensive
population-level study conducted through one-time censuses in urban India to
understand the ecoethology of free-ranging dogs. We built a model to test if
the observed groups could have been formed through random associations while
foraging. Our modeling results suggest that the dogs, like all efficient
scavengers, tend to forage singly but also form random uncorrelated groups. A
closer inspection of the group compositions however reveals that the foraging
associations are non-random events. The tendency of adults to associate with
the opposite sex in the mating season and of juveniles to stay close to adults
in the non-mating season drives the population towards aggregation, in spite of
the apparently random nature of the group size distribution. Hence we conclude
that to be or not to be social is a matter of choice for the free-ranging dogs,
and not a matter of chance.


title:
Spin-glass-like behavior in the spin turbulence of spinor Bose-Einstein
  condensates

abstract:
  We study numerically the spin turbulence in spin-1 ferromagnetic spinor
Bose-Einstein condensates (BECs). Spin turbulence (ST) is characterized by a
-7/3 power law in the spectrum of the spin-dependent interaction energy. The
direction of the spin density vector is spatially disordered but temporally
frozen in ST, showing some analogy with the spin glass state. Thus, we
introduce the order parameter of spin glass into ST in spinor BECs. When ST
develops through some instability, the order parameter grows with a -7/3 power
law, thus succeeding in describing ST well.


title:
G\"odel-type universes and chronology protection in Horava-Lifshitz
  gravity

abstract:
  In the attempts toward a quantum gravity theory, general relativity faces a
serious difficulty since it is non-renormalizable theory. Ho\v{r}ava-Lifshitz
gravity offers a framework to circumvent this difficulty, by sacrificing the
local Lorentz invariance at ultra-high energy scales in exchange of
power-counting renormalizability. The Lorentz symmetry is expected to be
recovered at low and medium energy scales. If gravitation is to be described by
a Ho\v{r}ava-Lifshitz gravity theory there are a number of issues that ought to
be reexamined in its context, including the question as to whether this gravity
incorporates a chronology protection, or particularly if it allows G\"odel-type
solutions with violation of causality. We show that Ho\v{r}ava-Lifshitz gravity
only allows hyperbolic G\"odel-type space-times whose essential parameters $m$
and $\omega$ are in the chronology respecting intervals, excluding therefore
any noncausal G\"odel-type space-times in the hyperbolic class. There emerges
from our results that the famous noncausal G\"odel model is not allowed in
Ho\v{r}ava-Lifshitz gravity. The question as to whether this quantum gravity
theory permits hyperbolic G\"odel-type solutions in the chronology preserving
interval of the essential parameters is also examined. We show that
Ho\v{r}ava-Lifshitz gravity not only excludes the noncausal G\"odel universe,
but also rules out any hyperbolic G\"odel-type solutions for physically
well-motivated perfect-fluid matter content.


title: Single-Neuron Criticality Optimizes Analog Dendritic Computation

abstract:
  Neurons are thought of as the building blocks of excitable brain tissue.
However, at the single neuron level, the neuronal membrane, the dendritic arbor
and the axonal projections can also be considered an extended active medium.
Active dendritic branchlets enable the propagation of dendritic spikes, whose
computational functions, despite several proposals, remain an open question.
Here we propose a concrete function to the active channels in large dendritic
trees. By using a probabilistic cellular automaton approach, we model the
input-output response of large active dendritic arbors subjected to complex
spatio-temporal inputs and exhibiting non-stereotyped dendritic spikes. We find
that, if dendritic spikes have a non-deterministic duration, the dendritic
arbor can undergo a continuous phase transition from a quiescent to an active
state, thereby exhibiting spontaneous and self-sustained localized activity as
suggested by experiments. Analogously to the critical brain hypothesis, which
states that neuronal networks self-organize near a phase transition to take
advantage of specific properties of the critical state, here we propose that
neurons with large dendritic arbors optimize their capacity to distinguish
incoming stimuli at the critical state. We suggest that "computation at the
edge of a phase transition" is more compatible with the view that dendritic
arbors perform an analog rather than a digital dendritic computation.

categories: q-bio.NC cond-mat.stat-mech nlin.AO physics.bio-ph q-bio.SC


title: Developing a General algorithm for Ball Curve with GC2

abstract:
  This paper dwells in developing a general algorithm for constructing a
piecewise Ball Curve with curvature continuity (GC2). The proposed algorithm
requires GC2 data in which the designer must define unit tangent vectors and
signed curvatures at each interpolating points. As a numerical example, a vase
is constructed using GC2 piecewise Ball Curve


title:
Chiral symmetry restoration at large chemical potential in strongly
  coupled SU(N) gauge theories

abstract:
  We show that at sufficiently large chemical potential SU(N) lattice gauge
theories in the strong coupling limit with staggered fermions are in a chirally
symmetric phase. The proof employs a polymer cluster expansion which exploits
the anisotropy between timelike and spacelike directions in the presence of a
quark chemical potential $\mu$. The expansion is shown to converge in the
infinite volume limit at any temperature for sufficiently large $\mu$. All
expectations of chirally non-invariant local fermion operators vanish
identically, or, equivalently, their correlations cluster exponentially, within
the expansion. The expansion itself may serve as a computational tool at large
$\mu$ and strong coupling.


title:
A Method Based on Total Variation for Network Modularity Optimization
  using the MBO Scheme

abstract:
  The study of network structure is pervasive in sociology, biology, computer
science, and many other disciplines. One of the most important areas of network
science is the algorithmic detection of cohesive groups of nodes called
"communities". One popular approach to find communities is to maximize a
quality function known as {\em modularity} to achieve some sort of optimal
clustering of nodes. In this paper, we interpret the modularity function from a
novel perspective: we reformulate modularity optimization as a minimization
problem of an energy functional that consists of a total variation term and an
$\ell_2$ balance term. By employing numerical techniques from image processing
and $\ell_1$ compressive sensing -- such as convex splitting and the
Merriman-Bence-Osher (MBO) scheme -- we develop a variational algorithm for the
minimization problem. We present our computational results using both synthetic
benchmark networks and real data.


title:
A New Analysis of Compressive Sensing by Stochastic Proximal Gradient
  Descent

abstract:
  In this manuscript, we analyze the sparse signal recovery (compressive
sensing) problem from the perspective of convex optimization by stochastic
proximal gradient descent. This view allows us to significantly simplify the
recovery analysis of compressive sensing. More importantly, it leads to an
efficient optimization algorithm for solving the regularized optimization
problem related to the sparse recovery problem. Compared to the existing
approaches, there are two advantages of the proposed algorithm. First, it
enjoys a geometric convergence rate and therefore is computationally efficient.
Second, it guarantees that the support set of any intermediate solution
generated by the proposed algorithm is concentrated on the support set of the
optimal solution.


title:
Long-time asymptotic for the derivative nonlinear Schr\"odinger equation
  with step-like initial value

abstract:
  We consider the Cauchy problem for the Gerdjikov-Ivanov(GI) type of the
derivative nonlinear Schr\"odinger (DNLS) equation:
$$iq_t+q_{xx}-iq^2\bar{q}_x+\frac{1}{2}|q|^4{q}=0.$$ with steplike initial
data: $q(x,0)=0$ for $x\le 0$ and $q(x,0)=Ae^{-2iBx}$ for $x>0$,where $A>0$ and
$B\in \R$ are constants.The paper aims at studying the long-time asymptotics of
the solution to this problem.We show that there are four regions in the
half-plane $-\infty<x<\infty,t>0$,where the asymptotics has qualitatively
different forms:a slowly decaying self-similar wave of Zakharov-Manakov type
for $x>-4tB$, a plane wave region:$x<-4t(B+\sqrt{2A^2(B+\frac{A^2}{4})})$, an
elliptic region:$-4t(B+\sqrt{2A^2(B+\frac{A^2}{4})})<x<-4tB$. The main tool is
the asymptotic analysis of an associated matrix Riemann-Hilbert problem.


title: What are Chinese Talking about in Hot Weibos?

abstract:
  SinaWeibo is a Twitter-like social network service emerging in China in
recent years. People can post weibos (microblogs) and communicate with others
on it. Based on a dataset of 650 million weibos from August 2009 to January
2012 crawled from APIs of SinaWeibo, we study the hot ones that have been
reposted for at least 1000 times. We find that hot weibos can be roughly
classified into eight categories, i.e. Entertainment & Fashion, Hot Social
Events, Leisure & Mood, Life & Health, Seeking for Help, Sales Promotion,
Fengshui & Fortune and Deleted Weibos. In particular, Leisure & Mood and Hot
Social Events account for almost 65% of all the hot weibos. This reflects very
well the fundamental dual-structure of the current society of China: On the one
hand, economy has made a great progress and quite a part of people are now
living a relatively prosperous and fairly easy life. On the other hand, there
still exist quite a lot of serious social problems, such as government
corruptions and environmental pollutions. It is also shown that users' posting
and reposting behaviors are greatly affected by their identity factors (gender,
verification status, and regional location). For instance, (1) Two thirds of
the hot weibos are created by male users. (2) Although verified users account
for only 0.1% in SinaWeibo, 46.5% of the hot weibos are contributed by them.
Very interestingly, 39.2% are written by SPA users. A more or less pathetic
fact is that only 14.4% of the hot weibos are created by grassroots (individual
users that are neither SPA nor verified). (3) Users from different areas of
China have distinct posting and reposting behaviors which usually reflect very
their local cultures. Homophily is also examined for people's reposting
behaviors.


title:
Black-hole perturbation theory: The asymptotic spectrum of the prolate
  spin-weighted spheroidal harmonics

abstract:
  Prolate spin-weighted spheroidal harmonics play a key role in black-hole
perturbation theory. In particular, the highly damped quasinormal resonances of
rotating Kerr black holes are closely related to the asymptotic eigenvalues of
these important functions. We here present a novel and compact derivation of
the asymptotic eigenvalues of the prolate spin-weighted spheroidal harmonics.
Our analysis is based on a simple trick which transforms the corresponding
spin-weighted spheroidal angular equation into a Schr\"odinger-like wave
equation which is amenable to a standard WKB analysis. Our analytical results
for the prolate asymptotic spectrum agree with previous numerical computations
of the eigenvalues which appear in the literature.

categories: gr-qc astro-ph.HE hep-th math-ph math.MP


title: Units of the String Link Monoids

abstract:
  We show that the map obtained by viewing a geometric (ie. representative)
braid as a string link induces an isomorphism of the n-strand braid group onto
the group of units of the n-strand string link monoid.


title:
Constrained LQR Design Using Interior-Point Arc-Search Method for Convex
  Quadratic Programming with Box Constraints

abstract:
  Although the classical LQR design method has been very successful in real
world engineering designs, in some cases, the classical design method needs
modifications because of the saturation in actuators. This modified problem is
sometimes called the constrained LQR design. For discrete systems, the
constrained LQR design problem is equivalent to a convex quadratic programming
problem with box constraints. We will show that the interior-point method is
very efficient for this problem because an initial interior point is available,
a condition which is not true for general convex quadratic programming problem.
We will devise an effective and efficient algorithm for the constrained LQR
design problem using the special structure of the box constraints and a
recently introduced arc-search technique for the interior-point algorithm. We
will prove that the algorithm is polynomial and has the best-known complexity
bound for the convex quadratic programming. The proposed algorithm is
implemented in MATLAB. An example for the constrained LQR design is provided to
show the effectiveness and efficiency of the design method. The proposed
algorithm can easily be used for model predictive control.


title: Rotating frame analysis of rigid body dynamics in space phasor variables

abstract:
  New method of analysing the free and heavy symmetric tops using Euler's
equations to perform extraction from the body frame to the lab frame.
Subsequent to extraction, the lab frame equations are solved by space phasor
method.


title:
A countable family of finitely presented infinite congruence-free
  monoids

abstract:
  We prove that monoids $\mathrm{Mon}\langle a,b,c,d : a^nb=0, ac=1, db=1,
dc=1, dab=1, da^2b=1, \ldots, da^{n-1}b=1\rangle$ are congruence-free for all
$n\geq 1$. This provides a new countable family of finitely presented
congruence-free monoids, bringing one step closer to understanding the
Boone--Higman Conjecture. We also provide examples which show that finitely
presented congruence-free monoids may have quadratic Dehn function.


title: On the pricing and hedging of options for highly volatile periods

abstract:
  Option pricing is an integral part of modern financial risk management. The
well-known Black and Scholes (1973) formula is commonly used for this purpose.
This paper is an attempt to extend their work to a situation in which the
unconditional volatility of the original asset is increasing during a certain
period of time. We consider a market suffering from a financial crisis. We
provide the solution for the equation of the underlying asset price as well as
finding the hedging strategy. In addition, a closed formula of the pricing
problem is proved for a particular case. The suggested formulas are expected to
make the valuation of options and the underlying hedging strategies during
financial crisis more precise.


title:
Radiation driven outflow in active galactic nuclei: the feedback effects
  of scattered and reprocessed photons

abstract:
  We perform time-dependent, 2DHD numerical simulations to study the dynamics
of a slowly rotating accretion flow from sub-pc to pc scales under the
irradiation from the central AGN. Compared to previous work, we improve the
calculation of the radiative force due to X-rays. More importantly, in addition
to radiative pressure and radiative heating/cooling directly from the central
AGN, in the momentum equation we also include the force due to the scattered
and reprocessed photons. We find that the accretion flow properties change
significantly due to this "re-radiation" effect. The inflow rate at the inner
boundary is reduced, while the outflow rate at the outer boundary is enhanced
by about one order of magnitude. This effect is more significant when the
density at the outer boundary is higher. The properties of outflows such as
velocity, momentum and energy fluxes, and the ratio of outflow rate and the
accretion rate, are calculated. We find that the efficiency of transferring the
radiation power into the kinetic power of outflow is typically $10^{-3}$, far
below the value of $\sim 0.05$ which is assumed in some cosmological
simulations. The effect of the temperature of the gas at the outer boundary
($T_0$) is investigated. When $T_0$ is high, the emitted luminosity of the
accretion flow oscillates. This is because in this case the gas around the
Bondi radius can be more easily heated to be above the virial temperature due
to its high internal energy. Another question we hope to address is the
so-called "sub-Eddington" puzzle. Observationally, the luminosity of almost all
AGNs are sub-Eddington, while theoretically the luminosity of an accretion flow
can easily be super-Eddington. We find that even when the re-radiation effect
is included and outflow does become much stronger, the luminosity, while
reduced, can still be super-Eddington.


title: On option pricing in illiquid markets with jumps

abstract:
  One of the shortcomings of the Black and Scholes model on option pricing is
the assumption that trading of the underlying asset does not affect the price
of that asset. This assumption can be fulfilled only in perfectly liquid
markets. Since most markets are illquid, this assumption might be too
restrictive. Thus, taking into account the price impact in option pricing is an
important issue. This issue has been dealt with, to some extent, for illiquid
markets by assuming a continuous process, mainly based on the Brownian motion.
However, the recent financial crisis and its effects on the global stock
markets have propagated the urgent need for more realistic models where the
stochastic process describing the price trajectories involves random jumps.
Nonetheless, works related to markets with jumps are scant compared to the
continuous ones. In addition, these previous studies do not deal with illiquid
markets. The contribution of this paper is to tackle the pricing problem for
options in illiquid markets with jumps as well as the hedging strategy within
this context, which is the first of its kind to the best knowledge.


title:
Efficient Calculation of Determinants of Symbolic Matrices with Many
  Variables

abstract:
  Efficient matrix determinant calculations have been studied since the 19th
century. Computers expand the range of determinants that are practically
calculable to include matrices with symbolic entries. However, the fastest
determinant algorithms for numerical matrices are often not the fastest for
symbolic matrices with many variables. We compare the performance of two
algorithms, fraction-free Gaussian elimination and minor expansion, on symbolic
matrices with many variables. We show that, under a simplified theoretical
model, minor expansion is faster in most situations. We then propose
optimizations for minor expansion and demonstrate their effectiveness with
empirical data.


title:
Local cohomology modules of a smooth Z-algebra have finitely many
  associated primes

abstract:
  Let $R$ be a commutative Noetherian ring that is a smooth $\mathbb
Z$-algebra. For each ideal $I$ of $R$ and integer $k$, we prove that the local
cohomology module $H^k_I(R)$ has finitely many associated prime ideals. This
settles a crucial outstanding case of a conjecture of Lyubeznik asserting this
finiteness for local cohomology modules of all regular rings.


title:
Structured Lattice Codes for Some Two-User Gaussian Networks with
  Cognition, Coordination and Two Hops

abstract:
  We study a number of two-user interference networks with multiple-antenna
transmitters/receivers, transmitter side information in the form of linear
combinations (over finite-field) of the information messages, and two-hop
relaying. We start with a Cognitive Interference Channel (CIC) where one of the
transmitters (non-cognitive) has knowledge of a rank-1 linear combination of
the two information messages, while the other transmitter (cognitive) has
access to a rank-2 linear combination of the same messages. This is referred to
as the Network-Coded CIC, since such linear combination may be the result of
some random linear network coding scheme implemented in the backbone wired
network. For such channel we develop an achievable region based on a few novel
concepts: Precoded Compute and Forward (PCoF) with Channel Integer Alignment
(CIA), combined with standard Dirty-Paper Coding. We also develop a capacity
region outer bound and find the sum symmetric GDoF of the Network-Coded CIC.
Through the GDoF characterization, we show that knowing "mixed data" (linear
combinations of the information messages) provides an unbounded spectral
efficiency gain over the classical CIC counterpart, if the ratio of SNR to INR
is larger than certain threshold. Then, we consider a Gaussian relay network
having the two-user MIMO IC as the main building block. We use PCoF with CIA to
convert the MIMO IC into a deterministic finite-field IC. Then, we use a linear
precoding scheme over the finite-field to eliminate interference in the
finite-field domain. Using this unified approach, we characterize the symmetric
sum rate of the two-user MIMO IC with coordination, cognition, and two-hops. We
also provide finite-SNR results which show that the proposed coding schemes are
competitive against state of the art interference avoidance based on orthogonal
access, for Rayleigh fading channels.


title:
The Symmetry Group of Lam\'e's System and the Associated Guichard Nets
  for Conformally Flat Hypersurfaces

abstract:
  We consider conformally flat hypersurfaces in four dimensional space forms
with their associated Guichard nets and Lam\'e's system of equations. We show
that the symmetry group of the Lam\'e's system, satisfying Guichard condition,
is given by translations and dilations in the independent variables and
dilations in the dependents variables. We obtain the solutions which are
invariant under the action of the 2-dimensional subgroups of the symmetry
group. For the solutions which are invariant under translations, we obtain the
corresponding conformally flat hypersurfaces and we describe the corresponding
Guichard nets. We show that the coordinate surfaces of the Guichard nets have
constant Gaussian curvature, and the sum of the three curvatures is equal to
zero. Moreover, the Guichard nets are foliated by flat surfaces with constant
mean curvature. We prove that there are solutions of the Lam\'e's system, given
in terms of Jacobi elliptic functions, which are invariant under translations,
that correspond to a new class of conformally flat hypersurfaces.


title: Thickness conditions and Littlewood--Paley sets

abstract:
  We consider sets in the real line that have Littlewood--Paley properties
$\mathrm{LP}(p)$ or $\mathrm{LP}$ and study the following question: How thick
can these sets be?


title: Spectral moments of trees with given degree sequence

abstract:
  Let $\lambda_1,\dots,\lambda_n$ be the eigenvalues of a graph $G$. For any
$k\geq 0$, the $k$-th spectral moment of $G$ is defined by
$\M_k(G)=\lambda_1^k+\dots+\lambda_n^k$. We use the fact that $\M_k(G)$ is also
the number of closed walks of length $k$ in $G$ to show that among trees $T$
whose degree sequence is $D$ or majorized by $D$, $\M_k(T)$ is maximized by the
greedy tree with degree sequence $D$ (constructed by assigning the highest
degree in $D$ to the root, the second-, third-, \dots highest degrees to the
neighbors of the root, and so on) for any $k\geq 0$. Several corollaries
follow, in particular a conjecture of Ili\'c and Stevanovi\'c on trees with
given maximum degree, which in turn implies a conjecture of Gutman, Furtula,
Markovi\'c and Gli\v{s}i\'c on the Estrada index of such trees, which is
defined as $\EE(G)=e^{\lambda_1}+\dots+e^{\lambda_n}$.


title:
Application of the inverse Hamiltonian method to Hartree-Fock-Bogoliubov
  calculations

abstract:
  We solve the Hartree-Fock-Bogoliubov (HFB) equations for a spherical mean
field and a pairing potential with the inverse Hamiltonian method, which we
have developed for the solution of the Dirac equation. This method is based on
the variational principle for the inverse Hamiltonian, and is applicable to
Hamiltonians that are bound neither from above nor below. We demonstrate that
the method works well not only for the Dirac but also for the HFB equations.


title: Morita theory for finitary 2-categories

abstract:
  We develop Morita theory for finitary additive 2-representations of finitary
2-categories. As an application we describe Morita equivalence classes for
2-categories of projective functors associated to finite dimensional algebras
and for 2-categories of Soergel bimodules.


title:
Compact surface Fano states embedded in the continuum of waveguide
  arrays

abstract:
  We describe theoretically and observe experimentally the formation of a
surface state in a semi-infnite waveguide array with side-coupled waveguide,
designed to simultaneously achieve Fano and Fabry-Perot resonances. We
demonstrate that the surface mode is compact, with all energy concentrated in
few waveguides at the edge and no field penetration beyond the side-coupled
waveguide position. Furthermore, we show that by broadening the spectral band
in the rest of the waveguide array it is possible to suppress exponentially
localized modes, whereas the Fano state having the eigenvalue embedded in the
continuum is preserved.


title: Classically conformal B-L extended Standard Model and phenomenology

abstract:
  Bardeen has argued that once the classically conformal invariance and its
minimal violation by quantum anomalies are imposed on the SM, it can be free
from the quadratic divergences and hence the gauge hierarchy problem. Under the
hypothesis, We investigated the minimal B-L extended SM with a flat Higgs
potential at the Planck scale. In this model, the B-L symmetry is radiatively
broken at TeV scale. We studied phenomenology and detectability of the model at
LHC and the ILC.


title:
Semiclassical analysis for Hamiltonian in the Born-Oppenheimer
  approximation

abstract:
  The purpose of this paper is to show that the operator \begin{equation*}
H\left(h\right) =-h^{2}\Delta_{x}-\Delta_{y}+V\left(x,y\right),
\end{equation*}% $V$ is continuous (or $V\in
L^{2}\left(\mathbb{R}_{x}^{n}\times \mathbb{R}%_{y}^{p}\right) $), and
$V\left(x,y\right) \rightarrow \infty $ as $% \left\Vert x\right\Vert
+\left\Vert y\right\Vert \rightarrow \infty,$ has purely discrete spectrum. We
give an application to the harmonic oscillator.


title:
A New Efficient Optimal Eighth-Order Iterative Method for Solving
  Nonlinear Equations

abstract:
  We established a new eighth-order iterative method, consisting of three
steps, for solving nonlinear equations. Per iteration the method requires four
evaluations (three function evaluations and one evaluation of the first
derivative). Convergence analysis shows that this method is eighth-order
convergent which is also substantiated through the numerical
works.Computational results ascertain that our method is efficient and
demonstrate almost better performance as compared to the other well known
eighth-order methods.


title: New Efficient Steffensen Type method for Solving Nonlinear Equations

abstract:
  In the present paper, by approximating the derivatives in the Kou et al.
\cite{Kou} fourth-order method by central difference quotient, we obtain new
modification of this method free from derivatives. We prove the important fact
that the method obtained preserve their order of convergence, without
calculating any derivative. Finally, numerical tests confirm that our method
give the better performance as compare to other well known Steffensen type
methods.


title:
Measuring and Modeling Behavioral Decision Dynamics in Collective
  Evacuation

abstract:
  Identifying and quantifying factors influencing human decision making remains
an outstanding challenge, impacting the performance and predictability of
social and technological systems. In many cases, system failures are traced to
human factors including congestion, overload, miscommunication, and delays.
Here we report results of a behavioral network science experiment, targeting
decision making in a natural disaster. In each scenario, individuals are faced
with a forced "go" versus "no go" evacuation decision, based on information
available on competing broadcast and peer-to-peer sources. In this controlled
setting, all actions and observations are recorded prior to the decision,
enabling development of a quantitative decision making model that accounts for
the disaster likelihood, severity, and temporal urgency, as well as competition
between networked individuals for limited emergency resources. Individual
differences in behavior within this social setting are correlated with
individual differences in inherent risk attitudes, as measured by standard
psychological assessments. Identification of robust methods for quantifying
human decisions in the face of risk has implications for policy in disasters
and other threat scenarios.


title: The Standard Model

abstract:
  We declare that we live in the quantum 4-dimensional Minkowski space-time
with, via the gauge principle, the force-fields gauge-group structure, $SU_c(3)
\times SU_L(2) \times U(1)$ applied to the quark world or $SU_L(2) \times U(1)
\times SU_f(3)$ applied to the lepton world, built-in from the very beginning.
The quark world with the triplets from the "quark" group $SU_Q(3)$ (used to be
called "flavor $SU(3)$ symmetry"), which is of nuclear sizes and is protected
by $SU_c(3) \times SU_L(2) \times U(1)$ (i.e. the (123) symmetry), can be seen
by our world, while the lepton world, as of atomic sizes and protected by
$SU_L(2) \times U(1) \times SU_f(3)$ or another (123) symmetry, can also be
seen, as singlets of the quark group $SU_Q(3)$, by our world. Apart from the
"ignition" term, the entire Standard Model is dimensionless and massless in the
quantum 4-dimensional Minkowski space-time; that is, all couplings are
dimensionless and there are no mass terms in the quantum 4-dimensional
Minkowski space-time.
  Therefore, there exist the well-studied $3^\circ \,K$ cosmic microwave
background (CMB) and the now clustered neutrino halos formed from cosmic
background (CB) neutrinos (of three flavors, and antineutrinos), both present
in the overall background of our Universe. In theory, it yields neutrino
oscillations, as some lepton-flavor-violating processes, in a natural manner.


title:
A study of pickup and signal processing for HLS-II bunch current
  measurement system

abstract:
  For the HLS-II bunch current measurement system, in order to obtain the
absolute value of bunch current, the calibration factor should be determined by
using DCCT. At the HLS storage ring, the stretch effect of bunch length is
observed and the change rate is about 19% when the bunch current decays over
time and this will affect the performance of bunch current detection. To
overcome the bunch stretch influence in the HLS-II bunch current measurement,
an evaluation about pickup type and signal processing is carried out.
Strip-line pickup and button pickup are selectable, and the theoretical
analysis and demonstration experiment are performed to find out an acceptable
solution for the bunch current measurement system at HLS-II. The experimental
data analysis shows that the normalized calibration factor will change by about
27% when the bunch length change by about 19% if using the button pickup and
processing by peak value of bunch signal, the influence will be reduced to less
2% if adopting the strip-line pickup and integral.


title:
Saturn layered structure and homogeneous evolution models with different
  EOSs

abstract:
  The core mass of Saturn is commonly assumed to be 10-25 ME as predicted by
interior models with various equations of state (EOSs) and the Voyager gravity
data, and hence larger than that of Jupiter (0-10 ME). We here re-analyze
Saturn's internal structure and evolution by using more recent gravity data
from the Cassini mission and different physical equations of state: the ab
initio LM-REOS which is rather soft in Saturn's outer regions but stiff at high
pressures, the standard Sesame-EOS which shows the opposite behavior, and the
commonly used SCvH-i EOS. For all three EOS we find similar core mass ranges,
i.e. of 0-20 ME for SCvH-i and Sesame EOS and of 0-17 ME for LM-REOS. Assuming
an atmospheric helium mass abundance of 18%, we find maximum atmospheric
metallicities, Zatm of 7x solar for SCvH-i and Sesame-based models and a total
mass of heavy elements, MZ of 25-30 ME. Some models are Jupiter-like. With
LM-REOS, we find MZ=16-20 ME, less than for Jupiter, and Zatm less than 3x
solar. For Saturn, we compute moment of inertia values lambda=0.2355(5).
Furthermore, we confirm that homogeneous evolution leads to cooling times of
only about 2.5 Gyr, independent on the applied EOS. Our results demonstrate the
need for accurately measured atmospheric helium and oxygen abundances, and of
the moment of inertia for a better understanding of Saturn's structure and
evolution.


title:
Controllability of optical bistability, cooling and entanglement in
  hybrid cavity optomechanical systems by nonlinear atom-atom interaction

abstract:
  We investigate the effects of atomic collisions as well as optomechanical
mirror-field coupling on the optical bistability in a hybrid system consisting
of a Bose-Einstein condensate inside a driven optical cavity with a moving end
mirror. It is shown that the bistability of the system can be controlled by the
s-wave scattering frequency which can provide the possibility of realizing a
controllable optical switch. On the other hand, by studying the effect of the
Bogoliubov mode, as a secondary mechanical mode relative to the mirror
vibrations, on the cooling process as well as the bipartite mirror-field and
atom-field entanglements we find an interpretation for the cooling of the
Bogoliubov mode. The advantage of this hybrid system in comparison to the bare
optomecanical cavity with a two-mode moving mirror is the controllability of
the frequency of the secondary mode through the s-wave scattering interaction.


title:
Detecting and polarizing nuclear spins with double resonance on a single
  electron spin

abstract:
  We report the detection and polarization of nuclear spins in diamond at room
temperature by using a single nitrogen-vacancy (NV) center. We use
Hartmann-Hahn double resonance to coherently enhance the signal from a single
nuclear spin while decoupling from the noisy spin-bath, which otherwise limits
the detection sensitivity. As a proof-of-principle we: (I) observe coherent
oscillations between the NV center and a weakly coupled nuclear spin, (II)
demonstrate nuclear bath cooling which prolongs the coherence time of the NV
sensor by more than a factor of five. Our results provide a route to nanometer
scale magnetic resonance imaging, and novel quantum information processing
protocols.


title:
Quantum information processing with trapped electrons and
  superconducting electronics

abstract:
  We describe a parametric frequency conversion scheme for trapped charged
particles which enables a coherent interface between atomic and solid-state
quantum systems. The scheme uses geometric non-linearities of the potential of
a coupling electrode near a trapped particle. Our scheme does not rely on
actively driven solid-state devices, and is hence largely immune to noise in
such devices. We present a toolbox which can be used to build electron-based
quantum information processing platforms, as well as quantum interfaces between
trapped electrons and superconducting electronics.


title:
Automated Switching System for Skin Pixel Segmentation in Varied
  Lighting

abstract:
  In Computer Vision, colour-based spatial techniquesoften assume a static skin
colour model. However, skin colour perceived by a camera can change when
lighting changes. In common real environment multiple light sources impinge on
the skin. Moreover, detection techniques may vary when the image under study is
taken under different lighting condition than the one that was earlier under
consideration. Therefore, for robust skin pixel detection, a dynamic skin
colour model that can cope with the changes must be employed. This paper shows
that skin pixel detection in a digital colour image can be significantly
improved by employing automated colour space switching methods. In the root of
the switching technique which is employed in this study, lies the statistical
mean of value of the skin pixels in the image which in turn has been derived
from the Value, measures as a third component of the HSV. The study is based on
experimentations on a set of images where capture time conditions varying from
highly illuminated to almost dark.


title:
Giant Magnetic Fluctuations at the Critical Endpoint in Insulating
  HoMnO3

abstract:
  Although abundant research has focused recently on the quantum criticality of
itinerant magnets, critical phenomena of insulating magnets in the vicinity of
critical endpoints (CEP's) have rarely been revealed. Here we observe an
emergent CEP at 2.05 T and 2.2 K with a suppressed thermal conductivity and
concomitant strong critical fluctuations evident via a divergent magnetic
susceptibility (e.g., chi''(2.05 T, 2.2 K)/chi''(3 T, 2.2 K)=23,500 %,
comparable to the critical opalescence in water) in the hexagonal insulating
antiferromagnet HoMnO3.


title:
Medium modifications of baryon properties in nuclear matter and
  hypernuclei

abstract:
  We study the medium modifications of baryon properties in nuclear many-body
systems, especially in $\Lambda$ hypernuclei. The nucleon and the $\Lambda$
hyperon are described in the Friedberg-Lee model as nontopological solitons
which interact through the self-consistent exchange of scalar and vector
mesons. The quark degrees of freedom are explicitly considered in the model, so
that the medium effects on baryons could be investigated. It is found that the
model can provide reasonable descriptions for nuclear matter, finite nuclei,
and $\Lambda$ hypernuclei. The present model predicts a significant increase of
the baryon radius in nuclear medium.


title:
Consistent analysis of neutral- and charged-current (anti)neutrino
  scattering off carbon

abstract:
  Good understanding of the cross sections for (anti)neutrino scattering off
nuclear targets in the few-GeV energy region is a prerequisite for the correct
interpretation of results of ongoing and planned oscillation experiments. To
clarify a possible source of disagreement between recent measurements of the
cross sections on carbon, we analyze the available data within an approach
based on the realistic spectral function of carbon, treating neutral-current
elastic (NCE) and charged-current quasielastic (CCQE) processes on equal
footing. We show that the axial mass from the shape analysis of the MiniBooNE
data is in good agreement with the results reported by the BNL E734 and NOMAD
Collaborations. However, the combined analysis of the NCE and CCQE data does
not seem to support the contribution of multinucleon final states being large
enough to explain the normalization of the MiniBooNE-reported cross sections.


title: Topological Raman Band in Carbon Nanohorn

abstract:
  Raman spectroscopy has been used in chemistry and physics to investigate the
fundamental process involving light and phonons (quantum of lattice vibration).
The carbon nanohorn introduces a new subject to Raman spectroscopy, namely
topology. We show theoretically that a photo-excited carrier with a non-zero
winding number activates a topological $D$ Raman band through the Aharonov-Bohm
effect. The topology-induced $D$ Raman band can be distinguished from the
ordinary $D$ Raman band for a graphene edge by its peak position.


title: On a criterion for the equality of Dedekind Sums

abstract:
  In [3] it was shown that the Dedekond sums $s(m_1,n)$ and $s(m_2,n)$ are
equal only if $(m_1m_2-1)(m_1-m_2)\equiv 0$ mod $n$. Here we show that the
latter condition is equivalent to $12s(m_1,n)-12s(m_2,n)\in \Z$. In addition,
we determine, for a given number $m_1$, the number of integers $m_2$ in the
range $0\le m_2<n$, $(m_1,m_2)=1$, such that $12s(m_1,n)-12s(m_2,n)\in \Z$,
provided that $n$ is square-free.


title: Galactic structure explained with dissipative mirror dark matter

abstract:
  Dissipative dark matter, such as mirror dark matter and related hidden sector
dark matter candidates, requires an energy source to stabilize dark matter
halos in spiral galaxies. It has been proposed previously that supernovae could
be the source of this energy. Recently, it has been argued that this mechanism
might explain two galactic scaling relations inferred from observations of
spiral galaxies. One of which is that $\rho_0 r_0$ is roughly constant, and
another relates the galactic luminosity to $r_0$. [$\rho_0$ is the dark matter
central density and $r_0$ is the core radius.] Here we derive equations for the
heating of the halo via supernova energy, and the cooling of the halo via
thermal bremsstrahlung. These equations are numerically solved to obtain
constraints on the $\rho_0, \ r_0$ parameters appropriate for spiral galaxies.
These constraints are in remarkable agreement with the aforementioned scaling
relations.


title:
Magnetic properties and Mott transition in the square-lattice Hubbard
  model with frustration

abstract:
  The magnetic properties and Mott transition of the Hubbard model on the
square lattice with frustration are studied at half-filling and zero
temperature by the variational cluster approximation. When the on-site
repulsion $U$ is large, magnetically disordered state is realized in highly
frustrated region between the N\'eel and collinear phases, and no
imcommensurate magnetic states are found there. As for the Mott transition, in
addition to the Mott gap and double occupancy, which clarify the nature of the
transition, the structure of the self-energy in the spectral representation is
studied in detail below and above the Mott transition point. The spectral
structure of the self-energy is almost featureless in the metallic phase, but
clear single dispersion, leading to the Mott gap, appears in the Mott insulator
phase.


title: Host Galaxies of Type Ia Supernovae from the Nearby Supernova Factory

abstract:
  We present photometric and spectroscopic observations of galaxies hosting
Type Ia supernovae (SNe Ia) observed by the Nearby Supernova Factory
(SNfactory). Combining GALEX UV data with optical and near infrared photometry,
we employ stellar population synthesis techniques to measure SN Ia host galaxy
stellar masses, star-formation rates (SFRs), and reddening due to dust. We
reinforce the key role of GALEX UV data in deriving accurate estimates of
galaxy SFRs and dust extinction. Optical spectra of SN Ia host galaxies are
fitted simultaneously for their stellar continua and emission lines fluxes,
from which we derive high precision redshifts, gas-phase metallicities, and
Halpha-based SFRs. With these data we show that SN Ia host galaxies present
tight agreement with the fiducial galaxy mass-metallicity relation from SDSS
for stellar masses log(M_*/M_Sun)>8.5 where the relation is well-defined. The
star-formation activity of SN Ia host galaxies is consistent with a sample of
comparable SDSS field galaxies, though this comparison is limited by systematic
uncertainties in SFR measurements. Our analysis indicates that SN Ia host
galaxies are, on average, typical representatives of normal field galaxies.


title:
Host Galaxy Properties and Hubble Residuals of Type Ia Supernovae from
  the Nearby Supernova Factory

abstract:
  We examine the relationship between Type Ia Supernova (SN Ia) Hubble
residuals and the properties of their host galaxies using a sample of 115 SNe
Ia from the Nearby Supernova Factory (SNfactory). We use host galaxy stellar
masses and specific star-formation rates fitted from photometry for all hosts,
as well as gas-phase metallicities for a subset of 69 star-forming (non-AGN)
hosts, to show that the SN Ia Hubble residuals correlate with each of these
host properties. With these data we find new evidence for a correlation between
SN Ia intrinsic color and host metallicity. When we combine our data with those
of other published SN Ia surveys, we find the difference between mean SN Ia
brightnesses in low and high mass hosts is 0.077 +- 0.014 mag. When viewed in
narrow (0.2 dex) bins of host stellar mass, the data reveal apparent plateaus
of Hubble residuals at high and low host masses with a rapid transition over a
short mass range (9.8 <= log(M_*/M_Sun) <= 10.4). Although metallicity has been
a favored interpretation for the origin of the Hubble residual trend with host
mass, we illustrate how dust in star-forming galaxies and mean SN Ia progenitor
age both evolve along the galaxy mass sequence, thereby presenting equally
viable explanations for some or all of the observed SN Ia host bias.


title:
Towards a better knowledge of the nuclear equation of state from the
  isoscalar breathing mode

abstract:
  The measurements of the isoscalar giant monopole resonance (GMR), also called
the breathing mode, are analyzed with respect to their constraints on the
quantity $M_c$, e.g. the density dependence of the nuclear incompressibility
around the so-called crossing density $\rho_c$=0.1 fm$^{-3}$. The correlation
between the centroid of the GMR, $E_\mathrm{GMR}$, and $M_c$ is shown to be
more accurate than the one between $E_\mathrm{GMR}$ and the incompressibility
modulus at saturation density, $K_\infty$, giving rise to an improved
determination on the nuclear equation of state. The relationship between $M_c$
and $K_\infty$ is given as a function of the skewness parameter $Q_\infty$
associated to the density dependence of the equation of state. The large
variation of $Q_\infty$ among different energy density functionnals directly
impacts the knowledge of $K_\infty$: a better knowledge of $Q_\infty$ is
required to deduce more accurately $K_\infty$. Using the Local Density
Approximation, a simple and accurate expression relating $E_\mathrm{GMR}$ and
the quantity $M_c$ is derived and successfully compared to the fully
microscopic predictions.


title: Wedge decomposition of polyhedral products

abstract:
  We prove that certain polyhedral products, including the moment-angle
complexes, for the Alexander duals of shellable and sequentially Cohen-Macaulay
complexes decompose into wedges of explicitly given suspension spaces, which
implies the properties of the Stanley-Reisner rings, known as Golod, of theses
complexes.