66,829 research outputs found
Implications of Z-normalization in the matrix profile
Companies are increasingly measuring their products and services, resulting in a rising amount of available time series data, making techniques to extract usable information needed. One state-of-the-art technique for time series is the Matrix Profile, which has been used for various applications including motif/discord discovery, visualizations and semantic segmentation. Internally, the Matrix Profile utilizes the z-normalized Euclidean distance to compare the shape of subsequences between two series. However, when comparing subsequences that are relatively flat and contain noise, the resulting distance is high despite the visual similarity of these subsequences. This property violates some of the assumptions made by Matrix Profile based techniques, resulting in worse performance when series contain flat and noisy subsequences. By studying the properties of the z-normalized Euclidean distance, we derived a method to eliminate this effect requiring only an estimate of the standard deviation of the noise. In this paper we describe various practical properties of the z-normalized Euclidean distance and show how these can be used to correct the performance of Matrix Profile related techniques. We demonstrate our techniques using anomaly detection using a Yahoo! Webscope anomaly dataset, semantic segmentation on the PAMAP2 activity dataset and for data visualization on a UCI activity dataset, all containing real-world data, and obtain overall better results after applying our technique. Our technique is a straightforward extension of the distance calculation in the Matrix Profile and will benefit any derived technique dealing with time series containing flat and noisy subsequences
Impact parameter dependent S-matrix for dipole-proton scattering from diffractive meson electroproduction
We extract the S-matrix element for dipole-proton scattering using the data
on diffractive electroproduction of vector mesons at HERA. By considering the
full t dependence of this process we are able to reliably unfold the profile of
the S-matrix for impact parameter values b>0.3 fm. We show that the results
depend only weakly on the choice of the form for the vector meson wave
function. We relate this result to the discussion about possible saturation
effects at HERA.Comment: 15 pages, 6 figure
A description of the Galactic Center excess in the Minimal Supersymmetric Standard Model
Observations with the Fermi Large Area Telescope (LAT) indicate an excess in
gamma rays originating from the center of our Galaxy. A possible explanation
for this excess is the annihilation of Dark Matter particles. We have
investigated the annihilation of neutralinos as Dark Matter candidates within
the phenomenological Minimal Supersymmetric Standard Model (pMSSM). An
iterative particle filter approach was used to search for solutions within the
pMSSM. We found solutions that are consistent with astroparticle physics and
collider experiments, and provide a fit to the energy spectrum of the excess.
The neutralino is a Bino/Higgsino or Bino/Wino/Higgsino mixture with a mass in
the range ~GeV or ~GeV annihilating into W bosons. A third
solutions is found for a neutralino of mass ~GeV annihilating into top
quarks. The best solutions yield a Dark Matter relic density . These pMSSM solutions make clear forecasts for LHC, direct and indirect
DM detection experiments. If the MSSM explanation of the excess seen by
Fermi-LAT is correct, a DM signal might be discovered soon.Comment: Large extension of previous paper: 2 more solutions found in the MSSM
(Bino-Higgsino, Bino-Wino-Higgsino into WW and Bino into ttbar), added
description on extra fit uncertainties, added description on flavor
observables, added discussion on dwarf limit
Transversity distributions in the nucleon in the large-N_c limit
We compute the quark and antiquark transversity distributions in the nucleon
at a low normalization point of 600 MeV in the large- limit, where the
nucleon can be described as a soliton of an effective chiral theory (chiral
quark-soliton model). The flavor-nonsinglet distributions, and , appear in leading order
of the -expansion, while the flavor-singlet distributions, and , are non-zero only in
next-to-leading order. The transversity quark and antiquark distributions are
found to be significantly different from the longitudinally polarized
distributions and , respectively, in contrast to the prediction of the naive
non-relativistic quark model. We show that this affects the predictions for the
spin asymmetries in Drell-Yan pair production in transversely polarized pp and
ppbar collisions.Comment: 45 pages, 16 figure
Evidence of Odderon-exchange from scaling properties of elastic scattering at TeV energies
We study the scaling properties of the differential cross section of elastic
proton-proton () and proton-antiproton () collisions at high
energies. We introduce a new scaling function, that scales -- within the
experimental errors -- all the ISR data on elastic scattering from
to GeV to the same universal curve. We explore the
scaling properties of the differential cross-sections of the elastic and
collisions in a limited TeV energy range. Rescaling the TOTEM
data from TeV to and TeV, and comparing it to D0
data at TeV, our results provide an evidence for a -channel
Odderon exchange at TeV energies, with a significance of at least 6.26.
We complete this work with a model-dependent evaluation of the domain of
validity of the new scaling and its violations. We find that the scaling
is valid, model dependently, within GeV TeV,
with a range gradually narrowing with decreasing colliding energies.Comment: Accepted in EPJ C, with typos fixed, reorganized institutions
updated, Appendix A, B, C, D, E added, 60 pages, 29 figures, 13 tables,
Odderon significance: 6.26 sigma, conclusions unchange
Bulk Fermions in Warped Models with a Soft Wall
We study bulk fermions in models with warped extra dimensions in the presence
of a soft wall. Fermions can acquire a position dependent bulk Dirac mass that
shields them from the deep infrared, allowing for a systematic expansion in
which electroweak symmetry breaking effects are treated perturbatively. Using
this expansion, we analyze properties of bulk fermions in the soft wall
background. These properties include the realization of non-trivial boundary
conditions that simulate the ones commonly used in hard wall models, the
analysis of the flavor structure of the model and the implications of a heavy
top. We implement a soft wall model of electroweak symmetry breaking with
custodial symmetry and fermions propagating in the bulk. We find a lower bound
on the masses of the first bosonic resonances, after including the effects of
the top sector on electroweak precision observables for the first time, of
m_{KK} \gtrsim 1-3 TeV at the 95% C.L., depending on the details of the Higgs,
and discuss the implications of our results for LHC phenomenology.Comment: 34 pages, 8 figure
Exact probability function for bulk density and current in the asymmetric exclusion process
We examine the asymmetric simple exclusion process with open boundaries, a
paradigm of driven diffusive systems, having a nonequilibrium steady state
transition. We provide a full derivation and expanded discussion and digression
on results previously reported briefly in M. Depken and R. Stinchcombe, Phys.
Rev. Lett. {\bf 93}, 040602, (2004). In particular we derive an exact form for
the joint probability function for the bulk density and current, both for
finite systems, and also in the thermodynamic limit. The resulting distribution
is non-Gaussian, and while the fluctuations in the current are continuous at
the continuous phase transitions, the density fluctuations are discontinuous.
The derivations are done by using the standard operator algebraic techniques,
and by introducing a modified version of the original operator algebra. As a
byproduct of these considerations we also arrive at a novel and very simple way
of calculating the normalization constant appearing in the standard treatment
with the operator algebra. Like the partition function in equilibrium systems,
this normalization constant is shown to completely characterize the
fluctuations, albeit in a very different manner.Comment: 10 pages, 4 figure
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