Modularity And Associated Tools As A Mean To Master Quality Of Complex Embedded Systems

International audienceIn line with its focus on quality, RENAULT has settled a special action plan to answer the burst of complexity of engine management systems : EMS 2010. It will allow us a very high mastery of complex systems’ development with limited efforts in term of development time or development costs. This will enabled us to concentrate our forces on the benefits for our customers. Its development has been supported by our main engine management systems’ suppliers and especially the CONTINENTAL company. The basic feature of EMS 2010 is a modular architecture. This architecture is answering functional and dysfunctional requirements, and takes into accounts the constraints of embedded real time applications. The main objective is to answer all our vehicle line-up technical definitions with a limited number of versions of standardized modules. These modules have a standardized interface and adapt themselves to several parameters thanks to a particular mechanism. The second objective is to have standard modules of code that can be re-used on all our engine management electronic control units (ECU). The modules are hardware independent, thanks to specific coding rules, and are “plugged” on the basic software of ECU. The key element is our shelf that records our modules, and all the data linked to their development and their validation, allowing a high level of mastery in their development. The basis of the shelf, is a configuration management tool ; it manages the different versions of the modules but also their automatic adaptation to vehicle and engine technical definition. It supports also the development processes of our modules and is structured according to our architecture

Dissipation mechanisms identification of soft hollow particle-dampers in honeycomb structures for micro-vibrations environment

Particle dampers are enclosures partially filled with metallic or glass small spheres, attached to the vibrating structure. This paper deals with replacing hard classical particles by soft hollow ones to maximize damping and mass ratio. Hence, one aspect of this damping method is obtained by mixing the kinetic energy conversion of the structure into heat(frictional losses and collisions) and the elastic energy conversion into heat (visco-elastic deformation). This study is oriented toward experimental and theoretical investigations in order to distinguish the dissipation phenomena. The experimental approach first relies on identification and, then, on validation applied on composite aluminum honeycomb plates. Indeed, equivalent viscous damping is identified on small honeycomb samples; then cantilever honeycomb beams are filled with particles and studied. Theoretically, beyond the nonlinear dissipation by impact and friction, these particles add a visco-elastic behavior. The shapes of the hysteretic loops highlight that this behavior is predominant. Hence, oscillators are added in the FE model and permit to consider the effect of the particles. These kinds of particle dampers are highly nonlinear as a function of excitation frequency and amplitudes. The aim of this study is to provide a structural damping solution for space applications which require high pointing stability to enhance mission performances. In this perspective, damping of micro-vibrations was thought as a possible application; nevertheless it is shown that best efficiency is achieved in high frequency range

Decent working time: New trends, new issues.

Includes selected papers from the 9th International Symposium on Working Time, Paris (2004), looking at the increasing use of results-based employment relationships for managers and professionals, and the increasing fragmentation of time to more closely tailor staffing needs to customer requirements (e.g., short-hours, part-time work). Moreover, as operating/opening hours rapidly expand toward a 24-hour and 7-day economy, the book considers how this has resulted in a growing diversification, decentralization, and individualization of working hours, as well as an increasing tension between enterprises' business requirements and workers' needs and preferences regarding their hours. It addresses issues such as increasing employment insecurity and instability, time-related social inequalities, particularly in relation to gender, workers' ability to balance their paid work with their personal lives, and the synchronization of working hours with social times, such as community activities. In addition, the book offers suggestions on how policy-makers, academics, and the social partners can together help further develop effective policies for advancing "decent working timeRéduction du temps de travail; Aménagement du temps de travail; Horaires de travail; Labor laws and legislation; Developed countries; Trend; Arrangement of working time; Flexible hours of work; Hours of work;

Decent working time in industrialized countries: issues, scopes and paradox

International audienceThis chapter attempts to analyse the ways in which the trends and stakes of working time have changed during recent decades (section 1.2). The utility of the concept of “decent working time” will then be examined in the light of these changes, by emphasizing its heuristic contribution, and the perspectives and implications that the term suggests in respect of working time policy (section 1.3). The limits and even the paradoxes of such a concept when applied to a heterogeneous world of national spaces can thus be stipulated. The paradoxes and contradictions of policies, in this case EU ones, will then be stressed (section 1.4). Finally, we will show how the notion of “decent working time” suggests some reconfigurations of these policies (section 1.5)

Travelling graphs for the forced mean curvature motion in an arbitrary space dimension

We construct travelling wave graphs of the form $z=-ct+\phi(x)$, $\phi: x \in \mathbb{R}^{N-1} \mapsto \phi(x)\in \mathbb{R}$, $N \geq 2$, solutions to the $N$-dimensional forced mean curvature motion $V_n=-c_0+\kappa$ ($c\geq c_0$) with prescribed asymptotics. For any 1-homogeneous function $\phi_{\infty}$, viscosity solution to the eikonal equation $|D\phi_{\infty}|=\sqrt{(c/c_0)^2-1}$, we exhibit a smooth concave solution to the forced mean curvature motion whose asymptotics is driven by $\phi_{\infty}$. We also describe $\phi_{\infty}$ in terms of a probability measure on $\mathbb{S}^{N-2}$.Comment: 36 pages, 6 figure

Decent working time. New trends, new Issues

International audienc

Geology and morphostructural evolution of Piton de la Fournaise

International audienceThe morphology of Piton de la Fournaise volcano results from the succession of construction, destruction and deformation processes that occurred since at least 530 ka. The chaotic surface of the gently dipping submarine flanks indicates that volcaniclastic deposits related to massive flank landslides and erosion cover most of the submarine flanks. Only a few seamounts like Cône Elianne and the submarine continuation of the rift zones are built by lava flows. In the subaerial domain, Piton de la Fournaise exhibits deeply incised canyons evidencing intense erosion and eastward verging scarps whose origin is still controversial. The different interpretations invoking flank landslides and/or summit collapse calderas are summarized. Geological data indicate a twofold construction of Piton de la Fournaise. Between 530 and 60 kyrs, the volcanic centre located in the current Plaine des Sables led to the building of the western part of the massif. The volcanic centre migrated eastwards to its current location, possibly at 60–40 kyrs. Then Piton de la Fournaise experienced caldera collapses and recurrent phreatomagmatic eruptions especially between 4880 and 2340 yr BP as evidenced by the Bellecombe ash deposit. Most of the recent volcanic activity is now currently focused restricted inside the Enclos Fouqué caldera where lava flow accumulation and rare explosive events built the 400-m-high Central Cone

Agrofesteries indonesiennes : contributions paysannes à la conservation des forêts naturelles et de leurs ressources

Agroforestry is a new approach which aims to reconciliate agricultural and forestry sciences. However, agroforestry is an old practice. In the humid areas of the tropical world, peasant agrosystems often associate annual crops and tree crops, agriculture and management of natural forests. The great diversity of forest environment and of agricultural systems in IncÎonesia gave rise to a variety of agroforestry practices, which range from fairly simple modifications of the forest ecosystem, or tree-crop enrichment fallows in shifting cultivation, to complex agroforests and sophisticated home-gardens. Facing the ever increasing problems due to deforestation and genetic erosion, village gardens in Java or complex agroforests in forest areas of Sumatra can contribute to the conservation of natural forests and of their resources. The traditional knowledge concerning utilization and management of trees, forest stuctures and sylvigenetic mechanisms, which peasants developped over centuries, is of great value. It could inspire programs involving both conservation and economie use of forests in the tropic