Search results for "Matching"
showing 10 items of 509 documents
Dispersion-to-spectrum mapping in nonlinear fibers based on optical wave-breaking
2013
In this work we recognize new strategies involving optical wave-breaking for controlling the output pulse spectrum in nonlinear fibers. To this end, first we obtain a constant of motion for nonlinear pulse propagation in waveguides derived from the generalized nonlinear Schrödinger equation. In a second phase, using the above conservation law we theoretically analyze how to transfer in a simple manner the group-velocity-dispersion curve of the waveguide to the output spectral profile of pulsed light. Finally, the computation of several output spectra corroborates our proposition.
Epoch Parameterization by Gabor Atom Density in Experimental Epilepsy
2007
An Electrocorticogram (ECoG), during an epilepsy episode can change dramatically from the normal state into a high amplitude low frequency signal and suddenly return to the normal sate. It is possible to identify some stages in the epilepsy seizure, the most representative of them: basal, preictal, ictal and posictal. ECoG are highly non periodical signals, so they are analyze with T-F algorithms, in order to follow up its frequency evolution through the seizure stages. Each seizure stage has different frequency components and they show up at different time. Experimental epilepsy produce by kindling model in rats is used; signals are recorded at cortex level. The ECoG is decompose by means …
Shape of crossover between mean-field and asymptotic critical behavior in a three-dimensional Ising lattice
1998
Recent numerical studies of the susceptibility of the three-dimensional Ising model with various interaction ranges have been analyzed with a crossover model based on renormalization-group matching theory. It is shown that the model yields an accurate description of the crossover function for the susceptibility.
The role of nonlinear optical absorption in narrowband difference-frequency terahertz-wave generation
2010
We present a general analysis of the influence of nonlinear optical absorption on terahertz generation via optical difference frequency generation, when reaching for the quantum conversion efficiency limit. By casting the equations governing the process in a suitably normalized form, including either two-photon- or three-photon-absorption terms, we have been able to plot universal charts for phase matched optical-to-terahertz conversion for different values of the nonlinear absorption coefficients. We apply our analysis to some experiments reported to date, in order to understand to what extent multiphoton absorption could have played a role and also to predict the maximum achievable conver…
Obesity under full fresh fruit and vegetable access conditions
2021
There is no agreement regarding the role of fresh fruit and vegetables’ affordability, accessibility and availability, or access in general, on obesity rates. In this article we investigated whether access to fresh fruit and vegetables is related to better biometric indicators such as weight and body mass index. Using mediation and matching methods and assuming that farmers and traditional market sellers have easy access to fruit and vegetables, we found that having better access is not associated to a reduction in weight or body mass index. Potential explanations for this result are that better access was not associated with fresh fruit and vegetables’ consumption and fruit and vegetables’…
Distribution of Heavy Metals in Marine Sediments of Palermo Gulf (Sicily, Italy)
2008
Concentrations of Cr, Cu, Hg, Pb and Zn have been measured, by atomic absorption spectrophotometry, in the fine fraction (<63 μm) of surface sediments collected in 30 sites in the Palermo Gulf (Sicily, Italy) in order to assess the levels and the spatial distribution of these elements. Enrichment factors calculated with respect to clean areas have been considered to discriminate between levels due to background or to pollution contributions. The sampling stations, which form a grid inside these areas, are characterized by geographic proximity and by the presence of pollution sources. Ratio matching technique along with hierarchical clustering, minimum spanning tree and principal component a…
Learning of regular expressions by pattern matching
1995
We consider the problem of restoring regular expressions from good examples. We describe a natural learning algorithm for obtaining a “plausible” regular expression from one example. The algorithm is based on finding the longest substring which can be matched by some part of the so far obtained expression. We believe that the algorithm to a certain extent mimics humans guessing regular expressions from the same sort of examples. We show that for regular expressions of bounded length successful learning takes time linear in the length of the example, provided that the example is “good”. Under certain natural restrictions the run-time of the learning algorithm is polynomial also in unsuccessf…
Cost-effectiveness of psychotropic polypharmacy in routine schizophrenia care. Results of the ELAN prospective observational trial
2018
Abstract Aims To analyse the costs and cost-effectiveness of psychotropic polypharmacy in comparison to antipsychotic monotherapy in patients with schizophrenia and schizo-affective disorder under real-world treatment conditions. Methods A prospective observational study including 374 adult psychiatric in-patients with schizophrenia or schizo-affective disorder was conducted. Psychotropic regimen, clinical outcomes, and quality of life were assessed before discharge and after 6, 12, 18, and 24 months. Costs and outcomes of psychotropic polypharmacy in comparison to antipsychotic monotherapy were analysed by means of mixed-effects regression models adjusted for propensity scores. Net-benefit…
High Wage Workers Match with High Wage Firms: Clear Evidence of the Effects of Limited Mobility Bias
2012
Positive assortative matching implies that high productivity workers and firms match together. However, there is almost no evidence of a positive correlation between the worker and firm contributions in two-way fixed-effects wage equations. This could be the result of a bias caused by standard estimation error. Using German social security records we show that the effect of this bias is substantial in samples with limited inter-firm movement. The correlation between worker and firm contributions to wage equations is unambiguously positive.
Effects of a French remedial program on pupils’ educational outcomes
2018
International audience; Few studies have examined the French “Networks for Specialized Assistance to Pupils in Difficulty” (Rased). In this article, we evaluate the impact of receiving Rased services in the first year of primary schooling on academic success. Using data from a national panel study, we find inconsistency in student selection within Rased. Using matching methods, our results reveal that pupils who benefited from the program school have a higher probability of grade repetition and obtain significantly lower scores on the third grade national assessment, particularly in mathematics, compared to pupils with similar characteristics who did not take part in the program. This impac…