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The commutator and brush of the motor are often worn during operation. The wear of commutator—brushes is influenced by various factors: current density, material, sliding speed, contact force, temperature, and environmental humidity, especially by humid tropical climate conditions. This affects directly wear, long life, and the reliability of commutator—brushes. This paper presents the results of the electrical sliding wear behavior of the graphite brushes when the temperature, the humidity of the humid tropical environment, and current change. According to experimental planning, the studies were conducted on graphite brushes with three input factors: the temperature of 25 °C, 40 °C, and 55 °C, relative humidity (RH) of 51%, 75%, and 99%, and current 5 A, 7.5 A, and 10 A. The results show that the specific wear-rate Ws increases when relative humidity, temperature, and current increase. When the brush works in extreme conditions, the specific wear-rate Ws will reach the maximum value and equal to about 5.37 times the Ws value in the best conditions in this experiment.

In this research, CeO2 modified SiO2 powder was prepared for electrodepositing ZnNi alloy–CeO2 modified SiO2 particle composite coatings. Corrosion behavior of the ZnNi/(SiO2)CeO2 composite coatings was studied by the potentiodynamic polarization method and neutral salt spray test. The results show that the composite coating obtained at the plating current density of 3 A/dm2 in 20 min has the chemical composition with the nickel content of 14.90 wt %, which is composed only of the gamma phase. This composite coating has the brightest surface and the best corrosion resistance. The coating has the largest polarization resistance of 2430.48 Ω cm2 from polarization curve and the time for appearing the first red rust spot on the surface of this coating is the longest, lasting 1008 h.

The effects of the number of substituents and molecular weight of polyamines in the non-cyanide alkaline plating bath on the morphology, brightness and bright ranges of zinc electrodeposited coating and cathodic polarization, cyclic voltammogram on the non-cyanide alkaline zinc plating process were investigated. Cathodic polarization measurements showed that the polyamines all increased cathodic polarization of the plating process and shifted the zinc reduced potential to a more negative direction. However, cycle voltammogram curves of the 5 continuous cycles shows that the quaternary polyamine Q7-20 has a more stable adsorption and desorption processes than the secondary polyamine Bt18 has.

International audience; Monitoring application services becomes more and more a transverse key activity in information systems. Beyond traditional system administration and load control, new activities such as autonomic management and decision making systems raise the stakes over monitoring requirements. In this paper, we present ADAMO, an adaptive monitoring framework that tackles different quality of information (QoI)-aware data queries over dynamic data streams and transform them into probe configuration settings under resource constraints. The framework relies on a constraint-solving approach as well as on a component-based approach in order to provide static and dynamic mechanisms with flexible data access for multiple clients with different QoI needs, as well as generation and configuration of QoS and QoI handling components. The monitoring framework also adapts to resource constraints.

Les travaux de ce stage consistent à étudier les techniques d'édition de document multimédia, le modèle d'édition de LimSee3, les propositions et les expérimentations d'exportation de document LimSee3 vers les formats de présentation multimédia. Nous présentons les différents modèles d'édition qui sont employés par les outils existants. En plus, nous examinons d'exportation de document LimSee3 vers le format de document multimédia comme SMIL et le format qui ne supporte pas directement d'expression temporelle comme XHTML. En fait, le processus d'exportation est complexe en raison de la diversité de format de présentation de document multimédia. Nous proposons deux approches d'exportation ; l'un utilise Java et l'autre utilise un format intermédiaire avec les feuilles XSL. Le résultat est un cadre d'application offert au service d'exportation et les exportateurs de document LimSee3 vers de formats SMIL, XHTML+CSS+JavaScript, et un ordonnanceur en JavaScript qui permet de rajouter les scénarios temporels aux documents XHTML.

Les travaux de ce stage consistent à étudier les techniques d'édition de document multimédia, le modèle d'édition de LimSee3, les propositions et les expérimentations d'exportation de document LimSee3 vers les formats de présentation multimédia. Nous présentons les différents modèles d'édition qui sont employés par les outils existants. En plus, nous examinons d'exportation de document LimSee3 vers le format de document multimédia comme SMIL et le format qui ne supporte pas directement d'expression temporelle comme XHTML. En fait, le processus d'exportation est complexe en raison de la diversité de format de présentation de document multimédia. Nous proposons deux approches d'exportation ; l'un utilise Java et l'autre utilise un format intermédiaire avec les feuilles XSL. Le résultat est un cadre d'application offert au service d'exportation et les exportateurs de document LimSee3 vers de formats SMIL, XHTML+CSS+JavaScript, et un ordonnanceur en JavaScript qui permet de rajouter les scénarios temporels aux documents XHTML.