467 research outputs found

    Remarks on global controllability for the shallow-water system with two control forces

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    In this paper we deal with the compressible Navier-Stokes equations with a friction term in one dimension on an interval. We study the exact controllability properties of this equation with general initial condition when the boundary control is acting at both endpoints of the interval. Inspired by the work of Guerrero and Imanuvilov in \cite{GI} on the viscous Burger equation, we prove by choosing irrotational data and using the notion of effective velocity developed in \cite{cpde,cras} that the exact global controllability result does not hold for any time TT

    The Calculus on Measure Chains

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    Contribution au pronostic de défaut dans les systèmes complexes par les techniques intelligentes

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    Nous avons présenté une nouvelle approche basée sur l'utilisation d'une méthode guidée par les données pour le pronostic des défauts. Cette méthode requiert des données décrivant le processus de dégradation. Lorsque les données sont insuffisantes, la prédiction des états devient difficile avec les modèles profonds de type mémoire à long terme (LSTM), qui nécessitent une quantité importante de données d'apprentissage. Pour résoudre ce problème de rareté des données dans la prédiction de la durée de vie restante (RUL), nous proposons d'adopter une stratégie d'augmentation des données. Les résultats obtenus sont démontrent que l'application d'une stratégie d'augmentation des données, peut améliorer les performances de prédiction de la RUL en utilisant les techniques LSTM. Nous avons validé cette approche en utilisant les données de la NASA Commercial Modular Aero-Propulsion System Simulation (C-MAPPS)

    Diagnosis of rotor fault using neuro-fuzzy inference system

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    The three-phase induction machines (IM) is large importance and are being widely used as electromechanical system device regarding for their robustness, reliability, and simple design with well developed technologies. This work presents a reliable method for diagnosis and detection of rotor broken bars faults in induction machine. The detection faults are based on monitoring of the current signal. Also the calculation of the value of relative energy for each level of signal decomposition using package wavelet, which will be useful as data input of adaptive Neuro-Fuzzy inference system (ANFIS). In this method, fuzzy logic is used to make decisions about the machine state. The adaptive Neuro-Fuzzy inference system is able to identify the IM bearing state with high precision. This technique is applied under the MATLAB®.Keywords: Induction Machine; Diagnosis; Detection; Neuro-Fuzzy inference system

    Effect of IL-1β and IL-1RN polymorphisms in carcinogenesis of the gastric mucosa in patients infected with Helicobacter pylori in Algeria

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    Background: Infection with Helicobacter pylori is considered a potential risk of developing gastric cancer in association with contributing host genetic factor. IL-1β and IL-1RN polymorphisms appear to maintain and promote Helicobacter pylori infection and to stimulate neoplastic growth of the gastric mucosa.Objective and methods: In order to elucidate the effect of these polymorphisms in combination with gastric cancer in a population from northwestern Algeria, a case-control study was carried out on 79 patients infected with H. pylori with chronic atrophic gastritis and/or gastric carcinoma, and 32 subjects were recruited as casecontrol. IL-1β-31 bi-allelic and IL-1β-511 bi-allelic polymorphisms and IL 1RN penta-allelic were genotyped.Results: IL-1β-31C was associated with an increased risk of developing gastric carcinoma (OR4.614 [1.4314.81], p = 0.01). However, IL-1RN2 heterozygous allele type was significantly associated with chronic atrophic gastritis (OR4.2 [1.233.61], p = 0.022). IL-1β-511T was associated with an increased risk of development of chronic atrophic gastritis (OR4.286 [1.5411.89], p = 0.005).Conclusion: IL-1β and IL-1RN polymorphisms associated with H. pylori infectioncontribute to the development of chronic atrophic gastritis and gastric carcinomas in an Algerian population. The alleles IL-1β-31C and IL-1RN were associated with an increased risk of developing gastric carcinoma, and IL-1β-511T with an increased risk of developing chronic atrophic gastritis with no significant association of developing gastric carcinoma.Keywords: gastric mucosa; Helicobacter pylori; IL-1β; IL-1R
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