55 research outputs found

    Ambient Vibration Based Damage Diagnosis Using Statistical Modal Filtering and Genetic Algorithm: A Bridge Case Study

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    The authors recently developed a damage identification method which combines ambient vibration measurements and a Statistical Modal Filtering approach to predict the location and degree of damage. The method was then validated experimentally via ambient vibration tests conducted on full-scale reinforced concrete laboratory specimens. The main purpose of this paper is to demonstrate the feasibility of the identification method for a real bridge. An important challenge in this case is to overcome the absence of vibration measurements for the structure in its undamaged state which corresponds ideally to the reference state of the structure. The damage identification method is, therefore, modified to adapt it to the present situation where the intact state was not subjected to measurements. An additional refinement of the method consists of using a genetic algorithm to improve the computational efficiency of the damage localization method. This is particularly suited for a real case study where the number of damage parameters becomes significant. The damage diagnosis predictions suggest that the diagnosed bridge is damaged in four elements among a total of 168 elements with degrees of damage varying from 6% to 18%

    Genetic characterization of Barbari goats using microsatellite markers

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    Genetic variation in Barbari goats, a highly prolific breed distributed widely in the northern part of India, known for better milk and meat quality, was studied as a part of genetic characterization and conservation. The genomic DNA from 50 unrelated Barbari goats were amplified via PCR with a panel of 21 microsatellite markers, and resolved through 6 per cent denaturing polyacrylamide gel electrophoresis followed by silver staining. The number of alleles ranged from 4 to 11, with allele sizes ranging from 88 to 220 bp. The distribution of allele frequencies was between 0.0104 and 0.5208. Polymorphism information content varied from 0.5563 to 0.8348. The population was not in Hardy-Weinberg equilibrium for all except two microsatellite loci (ILSTS044 and ILSTS060). The observed heterozygosity ranged from 0.8478 to 1.0000 while the expected heterozygosity ranged from 0.6208 to 0.8509. Based on the results of the present study, there is a good scope for exploiting the genetic variability in the Barbari goats for further improvement of performance

    Private and Secure Public-Key Distance Bounding: Application to NFC Payment

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    Distance-Bounding is used to defeat relay attacks. For wireless payment systems, the payment terminal is not always online. So, the protocol must rely on a public key for the prover (payer). We propose a generic transformation of a (weakly secure) symmetric distance bounding protocol which has no post-verification into wide-strong-private and secure public-key distance bounding

    A Forward Privacy Model for RFID Authentication Protocols

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    Part 3: Smart Cards and Embedded DevicesInternational audienceIn this paper, we propose a new variant of indistinguishability-based security model for the RFID authentication protocol, which allows an adversary to obtain an authentication result and secret key of a target tag. Ng et al. showed that symmetric-key based RFID authentication protocols cannot be resilient to the above information leakage simultaneously in the Paise-Vaudenay security model. We review the existing result and extend the Juels-Weis security model to satisfy these properties by using a suitable restriction. Moreover, we give two example protocols that satisfy the modified security model

    Ambient Vibration Based Damage Diagnosis Using Statistical Modal Filtering and Genetic Algorithm: A Bridge Case Study

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    The authors recently developed a damage identification method which combines ambient vibration measurements and a Statistical Modal Filtering approach to predict the location and degree of damage. The method was then validated experimentally via ambient vibration tests conducted on full-scale reinforced concrete laboratory specimens. The main purpose of this paper is to demonstrate the feasibility of the identification method for a real bridge. An important challenge in this case is to overcome the absence of vibration measurements for the structure in its undamaged state which corresponds ideally to the reference state of the structure. The damage identification method is, therefore, modified to adapt it to the present situation where the intact state was not subjected to measurements. An additional refinement of the method consists of using a genetic algorithm to improve the computational efficiency of the damage localization method. This is particularly suited for a real case study where the number of damage parameters becomes significant. The damage diagnosis predictions suggest that the diagnosed bridge is damaged in four elements among a total of 168 elements with degrees of damage varying from 6% to 18%

    TRAITEMENT PAR ÉPLÉRÉNONE DANS LA CHORIORÉTINITE SÉREUSE CENTRALE CHRONIQUE : À PROPOS DE 8 CAS

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    Introduction :La choriorĂ©tinite sĂ©reuse centrale est une affection oculaire relativement frĂ©quente. Il s’agit d’une maculopathiedu sujet jeune, caractĂ©risĂ©e par la prĂ©sence d’un dĂ©collement sĂ©reux rĂ©tinien (DSR) siĂ©geant habituellement aupĂŽle postĂ©rieur, associĂ© Ă  des modifications de l’épithĂ©lium pigmentaire. Il a Ă©tĂ© suggĂ©rĂ© que la CRSC pourrait rĂ©sulterd’une hyperactivation des rĂ©cepteurs de minĂ©ralocorticoides au niveau des vaisseaux choroidiens, et donc il a Ă©tĂ© supposĂ©que les antagonistes des rĂ©cepteurs aux minĂ©ralocorticoides pouvaient constituer un traitement de la CRSC. Nous avonsdonc Ă©valuĂ© l’efficacitĂ© et la tolĂ©rance de l’éplĂ©rĂ©none, un antagoniste des rĂ©cepteurs aux minĂ©ralocorticoides dans letraitement de la CRSC chronique.MatĂ©riels et mĂ©thodes : une Ă©tude prospective a Ă©tĂ© rĂ©alisĂ©e entre juillet 2016 et aout 2018 Ă  l’hĂŽpital militaire moulayismail de meknes, chez 8 patients traitĂ©s par Ă©plĂ©rĂ©none pour une CRSC chronique Ă©voluant depuis au moins 3 mois avecretentissement sur l’acuitĂ© visuelle, Ă  la dose de 50 mg par jour le premier mois puis 25 mg par jour pendant 2 mois. Pourchaque patient l’acuitĂ© visuelle et l’OCT maculaire (Ă©paisseur centrale de la rĂ©tine) Ă©taient Ă©valuĂ©s avant traitement puisĂ  1 et 3 mois.RĂ©sultats : L’ñge moyen des patients Ă©tait 45.5 ± 9.45. 6 hommes et 2 femmes. Aucun patient n’a rapportĂ© la notion deprise de corticoides. La durĂ©e moyenne de l’évolution de la pathologie avant mise sous traitement Ă©tait de 23.75 mois avecdes extrĂȘmes allant de 4 Ă  72 mois. Une nette amĂ©lioration de l’acuitĂ© visuelle (logMAR) a Ă©tĂ© constatĂ©e chez tous les patients: l’acuitĂ© visuelle moyenne est passĂ©e de 0.9 Ă  l’admission Ă  0.225 Ă  1mois (p :0.014) et Ă  0.125 Ă  3 mois (p : 0.013).L’épaisseur centrale moyenne de la rĂ©tine a diminuĂ© de 347 ± 94 ÎŒm (243-500) avant traitement, 246 ± 42 ÎŒm (180-311)Ă  1 mois et 216 ± 26 ÎŒm (191-232) Ă  3 mois (p : 0.026 et 0.01 respectivement) 3 patients prĂ©sentaient une disparitioncomplĂšte du DSR Ă  1 mois sans rĂ©cidive Ă  3 mois. 2 autres patients prĂ©sentaient une disparition complĂšte du DSR Ă  3 mois.Aucun effet secondaire nĂ©cessitant l’arrĂȘt du traitement n’a Ă©tĂ© constatĂ©.Discussion : La CRSC est une pathologie frĂ©quente dont la physiopathologie est encore mal comprise. Compte tenu del’évolution spontanĂ©ment favorable d’un grand nombre de CRSC aigues, l’abstention thĂ©rapeutique est la rĂšgle. Si le DSRpersiste plus de 3 mois, un traitement peut ĂȘtre envisagĂ©. Aucun consensus thĂ©rapeutique n’a pu ĂȘtre Ă©tabli Ă  ce jour,deux traitements sont couramment utilisĂ©s, la photocoagulation focale au laser argon et la photothĂ©rapie dynamique Ă  lavertĂ©porfine.Le traitement par les antagonistes des rĂ©cepteurs aux minĂ©ralocorticoĂŻdes semble ĂȘtre une option thĂ©rapeutique prometteuse.Conclusion : Dans notre Ă©tude, l’introduction de l’éplĂ©rĂ©none a engendrĂ© une importante amĂ©lioration tant sur le plananatomique que fonctionnel chez les patients ayant une CRSC chronique
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