Vieillesses d’aujourd’hui : les femmes aînées et leurs rapports aux temps

Malgré l’émergence d’une littérature visant à décrire la vieillesse contemporaine, nous en savons encore peu sur le quotidien des femmes aînées : à l’âge de la retraite et à celle du grand âge, que font-elles de leur temps? Comment appréhendent-elles la trame temporelle du vieillir? Cette contribution s’articule autour du rapport au temps des femmes âgées. Plus particulièrement, nous nous intéressons à leurs représentations sociales de la vieillesse et à la façon dont elles appréhendent ce cycle de vie. Nous nous attarderons également aux temps sociaux qui ponctuent cette période de vie aux troisième et quatrième âges.Despite the emergence of a literature designed to describe contemporary old age, we still know little about the daily lives of elderly women. Once retired, once really old, how do they spend their time? In what manner do they comprehend the temporal warp and woof of aging? This article is built round the relationship of elderly women with time. More especially, we are interested in their social representations of old age and in their understanding of this life cycle. We will also look at the social time that is woven sporadically into these later and final stages of life

La transmission des valeurs d’engagement des aînées à leur descendance : une étude de cas de deux lignées familiales

Cet article s'intéresse à la place et aux rôles des femmes de 65 ans et plus dans l'espace privé (au sein de la famille) et l'espace public (au sein des mouvements associatifs), sous l'angle de la transmission intergénérationnelle des valeurs d'engagement. À partir des lignées familiales de deux aînées actives et engagées, issues de milieux socioéconomiques différents, les auteures analysent les héritages qu'elles laissent à leur descendance (enfants et petits-enfants), en prêtant attention particulièrement aux dynamiques de la transmission et aux facteurs qui y sont associés. Nouveaux modèles d'autonomie, de liberté et aussi de vieillissement, ces aînées exercent une très grande influence dans leur famille. Les résultats mettent ainsi en évidence les valeurs et les savoirs qu'elles transmettent (respect des autres, altruisme, goût de l'action et de la culture), mais aussi leur réception et leur effet différenciés, selon un processus dynamique complexe dans lequel interviennent notamment l'histoire familiale, les liens de filiation et d'attachement et, bien entendu, l'individualisation des héritières et des héritiers.In this article, the authors analyze, from the data of a wide-ranging qualitative research, the phenomenon of the transmission of social commitment by elderly women to their children and their grandchildren. The results are based on the information provided by the descendants of two socially and politically involved grandmothers. How are these women, with socio-economic distinction, viewed by their children and grandchildren? Have their social commitment values been passed on or not? And if so, how is this transmission viewed and received? In an effort to understand the many facets of continuity and discontinuity that exist between generations, this exploration shows therefore, that inter-generational transmission is not one-dimensional, but is rather part of a complex social issue and must be seen as an interactive and dynamic process. From this perspective, descendants of the older generation inherit not only commitment practices, but also a world view and commitment-prone values

Caractérisation par RMN du solide des matrices de stockage solide de l'hydrogène

On peut distinguer trois moyens de stockage de l'hydrogène à bord d'un véhicule : sous forme liquide (à 20K sous 10 bars), sous forme comprimée (350 bars), ou dans des matériaux solides sous forme physisorbée ou chimisorbée. Nous nous sommes plus particulièrement intéressés à l'étude de ces matériaux solides. Parmi ceux cités dans la littérature, nous avons choisi d'étudier deux systèmes qui se prêtent bien à une étude RMN : les alanates et les clathrates. L'objectif de notre étude est le développement et la validation d'outils de caractérisation par spectroscopie et imagerie de résonance magnétique nucléaire (RMN) de la structure de matériaux pour le stockage de l'hydrogène, et de leur évolution au cours des cycles de charge/décharge. Les deux principaux volets de cette étude sont d'une part l'analyse de la structure locale des matériaux et la compréhension de ses éventuelles modifications, et d'autre part, l'analyse in-situ de la distribution et de la diffusion de l'hydrogène au sein du matériau de stockag

Mieux vivre la nature à travers une visite au musée

Comment rendre les approches des musées de sciences naturelles encore plus efficaces pour relier les humains à la nature ? Cette contribution propose quelques pistes en explorant des domaines et des approches qui pour la plupart se situent hors des sentiers habituels de la muséologie

Capteurs Intelligents : Nouvelles Technologies et Nouvelles Problématiques pour la Sûreté de Fonctionnement

New technology allows intelligent sensors by integrating new functionalities: error measure correction, self-calibration, self-diagnosis of measures and sensor status, reconfiguration, digital communication. Industrialists take advantage of more accurate measurements, cost reductions and use facilities. For industrial safety, new dependability issues appear. Some functionalities as self-diagnosis and digital communication seem to be in favour of control systems availability. On the other hand, the high amount of electronics and programmable units implies new failure causes and modes. Availability assessments of intelligent sensors are quite low in literature. Moreover, “intelligent” functionalities are usually not taken into account. In this paper, a discussion about dependability issues and modelling is presented. An approach is proposed. Both functional and structural decompositions of the system are included which allow representing sensor functionalities and types of dependencies. Failures make up the third part of the model. First analyses show the consequences of these failures on sensor functions and the corresponding failure modes during time. An infrared gas sensor is used for example. Some tools for availability assessment of complex systems can take advantage of these results, especially when dysfunctional behaviour is not well known

Fiabilité des Capteurs-Transmetteurs intégrant des Fonctionnalités Numériques

These works are part of a PhD thesis performed at the INERIS, under the scientific supervision of the UTT, and about the reliability of digital-based transmitters. These systems are commonly described as “intelligent” since they are able to perform innovative functionalities such as self-diagnoses, error measurement corrections, self-adjustments, and on-line reconfigurations. Moreover, they may take advantage of a bidirectional digital communication to perform “cooperating” operations. First, an “intelligent transmitter” modelling has been developed, which includes material and functional interactions, and reliability analyses have been proposed based on this model, dealing with uncertainties linked to system behaviours under faulty conditions. Then, “intelligent transmitters” taking part of control systems have been considered, taking the system elements interactions into account, as well as the process influences, using a dynamic reliability framework

Dependability Issues for Intelligent Transmitters and Reliability Pattern Proposal

International audienceNew technologies make way for "intelligent" transmitters by integrating new functionalities: error measurement corrections, self-adjustment, self-diagnosis for measurement and transmitter status, on-line reconfiguration, and digital bidirectional communication. Industrialists are taking advantage of more accurate measurements, cost reductions and facilities. For industrial risk prevention, new dependability issues are arising. Functionalities such as self-diagnosis and digital communication seem to be in favour of control systems availability. On the other hand, the high amount of electronics and programmable units implies new failure causes and modes which are usually not well known. In this paper, dependability issues for intelligent transmitters are discussed and a reliability model is proposed. By using a Goal Tree - Success Tree (GTST) technique, both functional and material aspects of an intelligent transmitter pattern are included. Material-material, material-function, and function-function relationships are then demonstrated in Master Logic Diagrams (MLD). These results are proposed as support for further case studies. For example, the impact of any material failure on any function, and the reliability of the main functions, can be assessed using this kind of model. Other dependability tools can take advantage of this reliability pattern, for example when the behavioural aspects of complex systems are undetermined

Reliability Study of an Intelligent Transmitter

International audienceAn intelligent transmitter reliability study has to deal with several issues: various interactions between both material elements and functions; behaviors of components as programmable units and software which are difficult to predict when faults or failures occur, as well as the consequences on functions processing. A “3-step model” is therefore proposed to include both functional and material aspects, using Goal Tree–Success Tree (GTST), and setting faults and failures as a third full part. Then, Master Logic Diagrams (MLD) aim to represent several types of relationships between faults or failures, material elements, and functions. Probabilities are used for MLD components to take the indeterminate relationships into account. Quantitative assessments are then performed, using an infrared gas transmitter as an example: total relationships between any fault or failure and any function, probabilities of malfunction and failure modes. Moreover, uncertainty analyses show that even if input relationship data are uncertain, precise results can be obtained. These properties make the proposed model especially suitable for evaluating the reliability of intelligent transmitters. Finally, some design issues are discussed, taking advantage of the proposed model

Design of complex safety-related systems in accordance with IEC 61508

International audienceAccording to IEC 61508, a safety-related system is regarded as type B if it presents a high complexity (i.e. the failure mode of at least one component is not well defined, or the behaviour under fault conditions cannot be completely determined), or if there is insufficient data to support claims for failure rates. This paper proposes a modelling method adapted to the evaluation of failure probabilities for systems with uncertain behaviour under fault conditions. To this aim, weighted “continuous gates” are introduced in a fault tree framework. By acting on weight values, it is then allowed to continuously graduate system part architectures between series and parallel structures. An intelligent transmitter is used as example. Probabilities of failure on demand are assessed, with both failure rates and behaviour uncertainty analyses. Results tend to show that the lack of knowledge in system behaviour can be partially handled by this kind of approach

Safety Instrumented System reliability evaluation with Influencing Factors

International audienceThe relevance of reliability evaluation strongly depends on the quality of input data as failure rates. Reliability data handbooks give generic values which do not often fit system specificities. This paper deals with influencing factors in order to take into account some aspects as design, environment and use in reliability evaluations. Once a definition and a classification are proposed, a brief review of existing models is presented. This paper also introduces a new failure rate evaluation with influencing factors especially developed for safety instrumented systems. The seven-step methodology combines both qualitative and quantitative analyses to compensate for a potential lack of feedback knowledge. Some criteria are used to set a failure rate within a prior interval, according to system conditions. An application regarding safety pressure relief valves is included. The expected better argued and accurate results aim at leading to a more efficient risk management