Self-learning approaches for real optical networks

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Self-learning approaches to facilitate the deployment of ML algorithms in real networks are analyzed and their performance evaluated through an illustrative use case. Results show large benefits of collective self-learning with centralized retraining.Peer ReviewedPostprint (author's final draft

Learning life cycle to speed up autonomic optical transmission and networking adoption

Autonomic optical transmission and networking requires machine learning (ML) models to be trained with large datasets. However, the availability of enough real data to produce accurate ML models is rarely ensured since new optical equipment and techniques are continuously being deployed in the network. One option is to generate data from simulations and lab experiments, but such data could not cover the whole features space and would translate into inaccuracies in the ML models. In this paper, we propose an ML-based algorithm life cycle to facilitate ML deployment in real operator networks. The dataset for ML training can be initially populated based on the results from simulations and lab experiments. Once ML models are generated, ML retraining can be performed after inaccuracies are detected to improve their precision. Illustrative numerical results show the benefits of the proposed learning cycle for general use cases. In addition, two specific use cases are proposed and demonstrated that implement different learning strategies: (i) a two-phase strategy performing out-of-field training using data from simulations and lab experiments with generic equipment, followed by an in-field adaptation to support heterogeneous equipment (the accuracy of this strategy is shown for a use case of failure detection and identification), and (ii) in-field retraining, where ML models are retrained after detecting model inaccuracies. Different approaches are analyzed and evaluated for a use case of autonomic transmission, where results show the significant benefits of collective learning.Peer ReviewedPostprint (published version

Predictive autonomic transmission for low-cost low-margin metro optical networks

Low-cost low-margin implementation plays an essential role in upgrading optical metro networks required for future 5G ecosystem. In this regard, low-resolution analog-to-digital converters can be used in coherent optical transponders to reduce cost and power consumption. However, the resulting transmission systems become more sensitive to physical layer fluctuations like the events caused by fiber stressing. Such fluctuations might have a strong impact on the quality of transmission (QoT) of the signals. To guarantee robust operation, soft decision forward error correction (FEC) techniques are required to guarantee zero post-FEC bit error rate (BER) transmission, which could increase the power consumption of the receiver and thus operational expenses. In this paper, we aim at minimizing power consumption while keeping zero post-FEC errors by means of a predictive autonomic transmission agent (ATA) based on machine learning. We present a sophisticated ATA model that, taking advantage of real-time monitoring of state of polarization traces and the corresponding pre-FEC BER, predicts the right FEC configuration for short-term operation, thus requiring minimum power consumption. In addition, we propose a complementary long-term prediction of excessive pre-FEC BER to enable remote reconfiguration at the transmitter side through the network controller. A set of experimental measurements is used to train and validate the proposed ATA system. Exhaustive numerical analysis allows concluding that ATA based on artificial neural network predictors achieves the maximum QoT robustness with 80% power consumption reductions compared to static FEC configuration.The research leading to these results has received funding from the European Commission for the H2020-ICT-2016-2 METRO-HAUL project (G.A. 761727), from the AEI/FEDER TWINS project (TEC2017-90097-R), and from the Catalan Institution for Research and Advanced Studies (ICREA).Peer ReviewedPostprint (author's final draft

Effects of passive and active leg movements to interrupt sitting in mild hypercapnia on cardiovascular function in healthy adults

Prolonged sitting in a mild hypercapnic environment impairs peripheral vascular function. The effects of sitting interruptions using passive or active skeletal muscle contractions are still unclear. Therefore, we sought to examine the vascular effects of brief periods (2 min every half hour) of passive and active lower limb movement to interrupt prolonged sitting with mild hypercapnia in adults. Fourteen healthy adults (24 ± 2 yr) participated in three experimental visits sitting for 2.5 h in a mild hypercapnic environment (CO2 = 1,500 ppm): control (CON, no limb movement), passive lower limb movement (PASS), and active lower limb movement (ACT) during sitting. At all visits, brachial and popliteal artery flow-mediated dilation (FMD), microvascular function, plasmatic levels of nitrate/nitrite and endothelin-1, and heart rate variability were assessed before and after sitting. Brachial and popliteal artery FMDs were reduced in CON and PASS (P \u3c 0.05) but were preserved (P \u3e 0.05) in ACT. Microvascular function was blunted in CON (P \u3c 0.05) but was preserved in PASS and ACT (P \u3e 0.05). In addition, total plasma nitrate/nitrite was preserved in ACT (P \u3e 0.05) but was reduced in CON and PASS (P \u3c 0.05), and endothelin-1 levels were decreased in ACT (P \u3c 0.05). Both passive and active movement induced a greater ratio between the low-frequency and high-frequency bands for heart rate variability (P \u3c 0.05). For the first time, to our knowledge, we found that brief periods of passive leg movement can preserve microvascular function, but that an intervention that elicits larger increases in shear rate, such as low-intensity exercise, is required to fully protect both macrovascular and microvascular function and circulating vasoactive substance balance

Application de la méthode d’immuno-diffusion en gélose au diagnostic expérimental d’infections à Herpesvirus bovis chez les Bovins (Rhinotrachéite infectieuse chez le veau, Balanoposthite chez le taureau)

D’exécution aisée, rapide, applicable au contrôle de sérums nombreux, la méthode d’immuno-diffusion en gélose apporte, dans le diagnostic expérimental et l’enquête épidémiologique d’infections à Herpesvirus bovis chez les Bovins (rhinotrachéite infectieuse, balanoposthites de taureaux) des résultats dont la signification (preuve de l’infection et de son caractère récent) est différente de ceux de la séro neutralisation

Présence, dans le sérum d’Ovins, d’anticorps inhibant l’hémagglutination par Myxovirus parainfluenzae

Dans un lot composé de trente brebis et de leurs agneaux, la pro portion des sujets dont le sérum inhibe, à des titres élevés de dilu tion, l’hémagglutination des érythrocytes de cobaye par une souche bovine de Myxovirus parainfluenzae dépasse 80 p. 100. Les résultats obtenus, en inhibition d’hémagglutination et en séro neutralisation, avec la fraction globulinique du sérum précipitable par le sulfate d’ammoniaque, sont quantitativement plus faibles, mais qualita tivement analogues

Variations dans le sérum de l'agneau du titre des anticorps inhibant l'hémagglutination par Myxovirus parainfluenzae au cours des trois premiers mois

Le titre des anticorps inhibant l’hémagglutination par Myxovi rus Parainfluenzae 3, nul chez l’agneau avant qu’il ait absorbé le colostrum maternel, s’élève dès les jours suivants et dépasse celui de la mère. Il diminue ensuite progressivement, rejoint celui de cette dernière au cours de la quatrième quinzaine et sa chute se poursuit au cours du troisième mois

Réponses, clinique et sérologique, du veau à l’inoculation par diverses voies (génitale, oculaire, pulmonaire) d’une souche d’Herpesvirus isolée d’une lésion de pneumonie du veau

Inoculée au veau, la souche HB 1 d 'Herpesvirus bovis, provoque des réactions cliniques et immunologiques dont l’analyse permet d’apprécier : a) l’influence de l’âge sur la réceptivité du veau, beaucoup plus faible à 6 mois qu’à la naissance, et celle de la voie d’inoculation sur la pathogénie et l’évolution clinique de l’infection ; b) des différences de nature dans l’immunité partielle conférée par une première inoculation, selon la voie par laquelle celle-ci est effectuée ; c) l’aspect cinétique de l’immunité humorale consécutive à l’infection expérimentale

Etude, en immuno-diffusion, de quelques propriétés antigéniques de souches de virus de « maladie muqueuse » bovine isolées en France

Faye P., Charton André, Bernard C., Le Layec Cl. Etude, en immuno-diffusion, de quelques propriétés antigéniques de souches de virus de «Maladie muqueuse» bovine isolées en France. In: Bulletin de l'Académie Vétérinaire de France tome 123 n°9, 1970. pp. 409-413