336 research outputs found
All-optical label swapping of in-band addresses and 160 Gbit/s data packets
A 1×4 all-optical packet switch is presented, based on an optical label swapping technique that utilises a scalable label processor and a label rewriter with 'on the fly' operation. Experimental results show error-free packet switching with a data payload at 160Gbit/s. The label erasing and new label insertion operation introduces 0.5dB of power penalty. These results indicate a potential utilisation of the presented technique in a multi-hop packet switched network
All-optical label swapping techniques for data packets beyond 160 Gb/s
We present two paradigms to realize all-optical packet switches, and report experimental results showing the routing operation of the 160 Gb/s packets and beyond. Photonic integrated sub-systems required to implement the packet switch are reviewed. © 2009 IEEE
Low penalty 80 Gb/s non-inverted wavelength conversion using a broad rectangular shaped optical filter
We demonstrate non-inverted wavelength conversion at 80 Gb/s based on cross-phase modulation in a SOA. Using a flat-top 6 nm broad filter with sharp roll-off we achieve a penalty of only 0.5 dB
Influence of seat-belt use on the severity of injury in traffic accidents
ABSTRACT: Background: About 1.35 million people died in traffic accidents around the world in 2018, make this type of accidents the 8th cause of death in the world. Particularly, in Spain, there were 204,596 traffic accidents during 2016 and 2017, out of which 349,810 drivers were injured. The objective of this study was to understand to what extent seat belt non-use and human factors contribute to drivers injury severity. Methodology: The results are based on the information and 2016-17 data provided by the Spain national traffic department "Dirección General de Tráfico" (DGT). The discretization model and Bayesian Networks were developed based on important variables from the literature. These variables were classified as; human factor, demographic factor, conditioning factor and seat belt use. Results: The results showed that failure to wear the seat belt by drivers are likely to increase the risk of fatal and sever injury significantly. Moreover, distraction and road type road can contribute to the accident severity
Analytical model for calculating the nonlinear distortion in silicon-based electro-optic Mach-Zehnder modulators
[EN] In this study, an analytical model for calculating the
nonlinear harmonic/intermodulation distortion for RF signals in
silicon-based electro-optic modulators is investigated by considering
the nonlinearity on the effective index change curve with the
operation point and the device structure simultaneously. Distortion
expressions are obtained and theoretical results are presented
showing that optimal modulator parameters can be found to linearize
it. Moreover, the harmonic distortion of a 1 mm silicon-based
asymmetric MZI is RF characterized and used to corroborate
the theoretical results. Based on the present model, the nonlinear
distortion in terms of bias voltage or operating wavelength
is calculated and validated by comparing with the experimental
data, showing a good agreement between measurements and
theory. Analog photonic link quality parameter like carrier-todistortion
is one of the parameters that can be found with that
model. Finally, the modulation depth is measured to assure that no
over-modulation is produced.This work was supported by the funding from the European Commission under project HELIOS (pHotonics Electronics functional Integration on CMOS), FP7-224312. The work of P. Sanchis and J.-M. Fedeli was supported by the funding funding from TEC2012-38540 LEOMIS, TEC2008-06333 SINADEC, and PROMETEO-2010-087. The work of F. Y. Gardes, D. J. Thomson and G. T. Reed was supported by funding received from the UK EPSRC funding body under the grant "UK Silicon Photonics."Gutiérrez Campo, AM.; Brimont, ACJ.; Herrera Llorente, J.; Aamer, M.; Thomson, DJ.; Gardes, FY.; Reed, GT.... (2013). Analytical model for calculating the nonlinear distortion in silicon-based electro-optic Mach-Zehnder modulators. Journal of Lightwave Technology. 31(23):3603-3612. https://doi.org/10.1109/JLT.2013.2286838S36033612312
Validation of spatial variability in downscaling results from the VALUE perfect predictor experiment
The spatial dependence of meteorological variables is crucial for many impacts, for example, droughts, floods, river flows, energy demand, and crop yield. There is thus a need to understand how well it is represented in downscaling (DS) products. Within the COST Action VALUE, we have conducted a comprehensive analysis of spatial variability in the output of over 40 different DS methods in a perfect predictor setup. The DS output is evaluated against daily precipitation and temperature observations for the period 1979?2008 at 86 sites across Europe and 53 sites across Germany. We have analysed the dependency of correlations of daily temperature and precipitation series at station pairs on the distance between the stations. For the European data set, we have also investigated the complexity of the downscaled data by calculating the number of independent spatial degrees of freedom. For daily precipitation at the German network, we have additionally evaluated the dependency of the joint exceedance of the wet day threshold and of the local 90th percentile on the distance between the stations. Finally, we have investigated regional patterns of European monthly precipitation obtained from rotated principal component analysis.
We analysed Perfect Prog (PP) methods, which are based on statistical relationships derived from observations, as well as Model Output Statistics (MOS) approaches, which attempt to correct simulated variables. In summary, we found that most PP DS methods, with the exception of multisite analog methods and a method that explicitly models spatial dependence yield unrealistic spatial characteristics. Regional climate model?based MOS methods showed good performance with respect to correlation lengths and the joint occurrence of wet days, but a substantial overestimation of the joint occurrence of heavy precipitation events. These findings apply to the spatial scales that are resolved by our observation network, and similar studies with higher resolutions, which are relevant for small hydrological catchment, are desirable.Funding Information: EU. Grant Number: EU COST Action ES110
Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC
The uncertainty on the calorimeter energy response to jets of particles is
derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the
calorimeter response to single isolated charged hadrons is measured and
compared to the Monte Carlo simulation using proton-proton collisions at
centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009
and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter
response to specific types of particles (positively and negatively charged
pions, protons, and anti-protons) is measured and compared to the Monte Carlo
predictions. Finally, the jet energy scale uncertainty is determined by
propagating the response uncertainty for single charged and neutral particles
to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3%
for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table,
submitted to European Physical Journal
Measurement of χ c1 and χ c2 production with s√ = 7 TeV pp collisions at ATLAS
The prompt and non-prompt production cross-sections for the χ c1 and χ c2 charmonium states are measured in pp collisions at s√ = 7 TeV with the ATLAS detector at the LHC using 4.5 fb−1 of integrated luminosity. The χ c states are reconstructed through the radiative decay χ c → J/ψγ (with J/ψ → μ + μ −) where photons are reconstructed from γ → e + e − conversions. The production rate of the χ c2 state relative to the χ c1 state is measured for prompt and non-prompt χ c as a function of J/ψ transverse momentum. The prompt χ c cross-sections are combined with existing measurements of prompt J/ψ production to derive the fraction of prompt J/ψ produced in feed-down from χ c decays. The fractions of χ c1 and χ c2 produced in b-hadron decays are also measured
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