Recent Results From the EU POF-PLUS Project: Multi-Gigabit Transmission Over 1 mm Core Diameter Plastic Optical Fibers

Recent activity to achieve multi-gigabit transmission over 1 mm core diameter graded-index and step-index plastic optical fibers for distances up to 50 meters is reported in this paper. By employing a simple intensity-modulated direct-detection system with pulse amplitude or digital multi-tone modulation techniques, low-cost transceivers and easy to install large-core POFs, it is demonstrated that multi-gigabit transmission up to 10 Gbit/s over 1-mm core diameter POF infrastructure is feasible. The results presented in this paper were obtained in the EU FP7 POF-PLUS project, which focused on applications in different scenarios, such as in next-generation in-building residential networks and in datacom applications

DREPANOCYTOSE SC REVELEE PAR UNE OSTEONECROSE DE LA TETE HUMERALE EN POST PARTUM

The double heterozygocity point SC occupies the second place of sickle cell disease syndromes major. The diagnosis, often late, is usually asked on the occasion of a complication. The association "sickle cell anemia-pregnancy" causes the alteration of maternal prognosis on the slope and haematological fetal on the plan midwifery. Among the maternal complications related to this pathology, are found the crises vasoocclusives with the bilateral necrosis of femoral heads or heads of humerales, These crises are all the more serious in that they can be complicated by syndromes acute chest in report with a pulmonary embolism greasy or deadly syndrome vasculorenal. The support of such a haemoglobinopathy need a prophylactic transfusion or better an exchange transfusion of the 28th week of gestation to obtain a rate of HbA greater than 50%. In postpartum, the risk of complications is increased, the systematic support should include even in the early days, warming, oxygenation, hydration hydro-electrolytic and sy.La double hétérozygotie SC occupe la deuxième place des syndromes drépanocytaires majeures. Le diagnostic, souvent tardif, est habituellement posé à l’occasion d’une complication. L’association « drépanocytose-grossesse » entraîne l’altération du pronostic maternel sur le versant hématologique et fœtal sur le plan obstétrical. Parmi les complications maternelles liées à cette pathologie, sont retrouvées les crises vasoocclusives avec la nécrose bilatérale des têtes fémorales ou des têtes humérales, notamment en post partum, tel chez notre jeune patiente. Ces crises sont d’autant plus graves qu’elles peuvent se compliquer de syndromes thoraciques aigus en rapport avec une embolie pulmonaire graisseuse mortelle ou de syndrome vasculorénal. La prise en charge d’une telle hémoglobinopathie nécessite une transfusion prophylactique ou mieux un échange transfusionnel dès la 28ème semaine d’aménorrhée pour obtenir un taux d’ HbA supérieur à 50%. En post-partum, le risque de complications est accrue, la prise en charge systématique doit comprendre, dés les premiers jours, un réchauffement, une oxygénation, une hydratation hydro-éléctrolytique et une antibiothérapie systématique

Formal verification of safety protocol in train control system

In order to satisfy the safety-critical requirements, the train control system (TCS) often employs a layered safety communication protocol to provide reliable services. However, both description and verification of the safety protocols may be formidable due to the system complexity. In this paper, interface automata (IA) are used to describe the safety service interface behaviors of safety communication protocol. A formal verification method is proposed to describe the safety communication protocols using IA and translate IA model into PROMELA model so that the protocols can be verified by the model checker SPIN. A case study of using this method to describe and verify a safety communication protocol is included. The verification results illustrate that the proposed method is effective to describe the safety protocols and verify deadlocks, livelocks and several mandatory consistency properties. A prototype of safety protocols is also developed based on the presented formally verifying method

Crosstalk Models for Short VDSL2 Lines from Measured 30 MHz Data

<p/> <p>In recent years, there has been a growing interest in hybrid fiber-copper access solutions, as in fiber to the basement (FTTB) and fiber to the curb/cabinet (FTTC). The twisted pair segment in these architectures is in the range of a few hundred meters, thus supporting transmission over tens of MHz. This paper provides crosstalk models derived from measured data for quad cable, lengths between 75 and 590 meters, and frequencies up to <inline-formula><graphic file="1687-6180-2006-085859-i1.gif"/></inline-formula> MHz. The results indicate that the log-normal statistical model (with a simple parametric law for the frequency-dependent mean) fits well up to <inline-formula><graphic file="1687-6180-2006-085859-i2.gif"/></inline-formula> MHz for both FEXT and NEXT. This extends earlier log-normal statistical modeling and validation results for NEXT over bandwidths in the order of a few MHz. The fitted crosstalk power spectra are useful for modem design and simulation. Insertion loss, phase, and impulse response duration characteristics of the direct channels are also provided.</p