Search results for "Signal processing"
showing 10 items of 2451 documents
Detailed studies of $^{100}$Mo two-neutrino double beta decay in NEMO-3
2019
The full data set of the NEMO-3 experiment has been used to measure the half-life of the two-neutrino double beta decay of $^{100}$Mo to the ground state of $^{100}$Ru, $T_{1/2} = \left[ 6.81 \pm 0.01\,\left(\mbox{stat}\right) ^{+0.38}_{-0.40}\,\left(\mbox{syst}\right) \right] \times10^{18}$ y. The two-electron energy sum, single electron energy spectra and distribution of the angle between the electrons are presented with an unprecedented statistics of $5\times10^5$ events and a signal-to-background ratio of ~80. Clear evidence for the Single State Dominance model is found for this nuclear transition. Limits on Majoron emitting neutrinoless double beta decay modes with spectral indices of …
Searches for Sterile Neutrinos with the IceCube Detector
2016
The IceCube neutrino telescope at the South Pole has measured the atmospheric muon neutrino spectrum as a function of zenith angle and energy in the approximate 320 GeV to 20 TeV range, to search for the oscillation signatures of light sterile neutrinos. No evidence for anomalous $\nu_\mu$ or $\bar{\nu}_\mu$ disappearance is observed in either of two independently developed analyses, each using one year of atmospheric neutrino data. New exclusion limits are placed on the parameter space of the 3+1 model, in which muon antineutrinos would experience a strong MSW-resonant oscillation. The exclusion limits extend to $\mathrm{sin}^2 2\theta_{24} \leq$ 0.02 at $\Delta m^2 \sim$ 0.3 $\mathrm{eV}^…
Structure of pion photoproduction amplitudes
2018
We derive and apply the finite energy sum rules to pion photoproduction. We evaluate the low energy part of the sum rules using several state-of-the-art models. We show how the differences in the low energy side of the sum rules might originate from different quantum number assignments of baryon resonances. We interpret the observed features in the low energy side of the sum rules with the expectation from Regge theory. Finally, we present a model, in terms of a Regge-pole expansion, that matches the sum rules and the high-energy observables.
Misión FLEX (Fluorescence Explorer): Observación de la fluorescencia por teledetección como nueva técnica de estudio del estado de la vegetación terr…
2014
[EN] FLEX (Fluorescence EXplorer) is a candidate for the 8th ESA’s Earth Explorer mission. Is the first space mission specifically designed for the estimation of vegetation fluorescence on a global scale. The mission is proposed to fly in tandem with the future ESA´s Sentinel-3 satellite. It is foreseen that the information obtained by Sentinel-3 will be supplemented with that provided by FLORIS (Fluorescence Imaging Spectrometer) onboard FLEX. FLORIS will measure the radiance between 500 and 800 nm with a bandwidth between 0.1 nm and 2 nm, providing images with a 150 km swath and 300 m pixel size. This information will allow a detailed monitoring of vegetation dynamics, by improving the me…
Superbeams plus neutrino factory: The golden path to leptonic CP violation
2002
Superbeams (SB) and Neutrino Factories (NF) are not alternative facilities for exploring neutrino oscillation physics, but successive steps. The correct strategy is to contemplate the combination of their expected physics results. We show its important potential on the disappearance of fake degenerate solutions in the simultaneous measurement of $\theta_{13}$ and leptonic CP violation. Intrinsic, sign($\Delta m_{13}^2$) and $\theta_{23}$ degeneracies are shown to be extensively eliminated when the results from one NF baseline and a SB facility are combined. A key point is the different average neutrino energy and baseline of the facilities. For values of $\theta_{13}$ near its present limit…
Thermal damage of the inner vein wall during endovenous laser treatment: key role of energy absorption by intravascular blood.
2002
background. Despite the clinical efficacy of endovenous laser treatment (EVLT), its mode of action is incompletely understood. objective. To evaluate the role of intravascular blood for the effective transfer of thermal damage to the vein wall through absorption of laser energy. methods. Laser energy (15 J/pulse, 940 nm) was endovenously administered to explanted greater saphenous vein (GSV) segments filled with blood (n = 5) or normal saline (n = 5) in addition to GSVs under in vivo conditions immediately prior to stripping. Histopathology was performed on serial sections to examine specific patterns of damage. Furthermore, in vitro generation of steam bubbles by different diode lasers (81…
Small bowel motility: relationship between smooth muscle contraction and electroenterogram signal.
2000
A study is made to correlate the electrical and mechanical activity of the smooth muscle of the small bowel. Bioelectrical signal recording from the intestinal serosa (electroenterogram) comprises a slow wave (SW) and spike burst (SB), though only the latter reflects intestinal pressure. The electroenterogram and smooth muscle pressure are simultaneously recorded in the canine small bowel. Spectral and time series analysis of the electroenterogram are performed to establish those electrical parameters that best reflect intestinal pressure. The results reveal an underlying correlation between the estimated parameters of electrical activity and smooth muscle pressure. In addition, parameters …
Correlation of oscillatory behaviour in Matlab using wavelets
2014
Here we present a novel computational signal processing approach for comparing two signals of equal length and sampling rate, suitable for application across widely varying areas within the geosciences. By performing a continuous wavelet transform (CWT) followed by Spearman?s rank correlation coefficient analysis, a graphical depiction of links between periodicities present in the two signals is generated via two or three dimensional images. In comparison with alternate approaches, e.g., wavelet coherence, this technique is simpler to implement and provides far clearer visual identification of the inter-series relationships. In particular, we report on a Matlab? code which executes this tec…
Digital estimators of relaxation spectra
2007
Determination of the distribution of relaxation times (DRT) from a wide variety of the time- and the frequency-domain material functions, such as polarization current and charge, real and imaginary parts of complex dielectric permittivity and complex dielectric modulus, the appropriate mechanical and magnetic counterparts is generalized as a filtering problem on a logarithmic time or frequency scale. Algorithms of the appropriate digital DRT estimators are derived. A novel regularization strategy is proposed based on choosing sampling rate for the input data, which ensures acceptably low random error of the recovered spectra. Optimum frequency ranges and sampling rates are found for determi…
Barnidipine block of L-type Ca2+ channel currents in rat ventricular cardiomyocytes
2000
The effects of barnidipine and nifedipine on L-type Ca2+ current (ICa(L)) were investigated in ventricular cardiomyocytes from rats. Both barnidipine and nifedipine reduced ICa(L) in a concentration and voltage dependent manner; the EC50 were 80 and 130 nM at a holding potential of −80 mV, respectively, and 18 and 6 nM at −40 mV, respectively. Both drugs induced a leftward shift of the steady-state inactivation curve of ICa(L). Using a twin pulse protocol, the relationships between the amount of block of ICa(L) by either drug, seen during the second pulse, and the length of the first pulse were described by monoexponential functions reflecting onset of block, dependent on drug concentration…