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International audienceIn this article, the problem of building a model in support of maintenance optimization when the only available information is that elicited from one expert is tackled. In particular, the degradation process affecting the component is modeled by resorting to the concept of effective age. Information is elicited from one expert by following a systematic literature approach, and the theoretical framework of fuzzy logic is used to deal with his or her qualitative statements. A hybrid approach based on Monte Carlo method and fuzzy logic is then applied to evaluate the performance of a given maintenance policy. Finally, the proposed methodology is applied to a real case study dealing with a medium-voltage test network

An integrated portable measurement system is described for the study of high speed and high temperature unsteady plasma flows such as those found in the vicinity of high current switching arcs. An array of optical fibers allows the formation of low spatial resolution images, with a maximum capture rate of 1 million images per second (1MHz), with 8 bit intensity resolution. Novel software techniques are reported to allow imaging of the arc; and to measure arc trajectories. Results are presented on high current (2kA) discharge events in a model test fixture and on the application to a commercial low voltage circuit breaker.

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Modeling the degradation process of a component is a fundamental issue for maintenance policy definition. In this work, a degradation model based on the concept of component "effective age" is proposed. The effective age of a component is treated like a physical variable, indicative of its degradation state, and allows to describe the fact that age may evolve faster or slower than chronological time in adverse or favorable working conditions, respectively. Under this concept, the objective of degradation modeling becomes the identification of the relations between the environmental and operating conditions of the component and its effective age. In particular, the proposed degradation modeling paradigm is thought to be applied to the situation, very common in practice, in which the only available information to build the model is that elicited from experts. The proposed modeling framework is applied to a real case study of a medium voltage test network.