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Qui protège la montagne sacrée ? Entre pressions géopolitiques et économiques et défi écologique, le rôle des ingénieurs à Taïwan
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A Survey on Flash-Memory Storage Systems: A Host-Side Perspective
No full textInternational audienceNAND flash memory has become the dominant storage media choice in a vast majority of application scenarios. Compared to mechanical hard disks, flash offers better access performance, energy efficiency, and shock resistance. However, the unique hardware peculiarities of this technology require dedicated facilities to manage the flash space and data. The implementation of flash management facilities has alternatively been realized either at the device or host computer level. Managing flash on the device side eases integration/compatibility and increases performance in certain scenarios. However, the limited computing resources inherent to devices and the lack of higher-level file system/application information make these solutions suboptimal in many situations. Managing flash on the host allows leveraging its abundant resources, and host-side knowledge such as data access patterns can be exploited to optimize flash management, at the cost of increased host-side complexity. The pros and cons of each approach also led to the appearance of hybrid, cross-layer solutions, enabling the collaboration of different layers of the storage stack. Recently, the pressure on modern storage systems requires that an increasing amount of flash management responsibilities is offloaded to the host, and the development of application-specific cross layer solutions: in that context, it is crucial to review these developments. In this paper, we make a comprehensive survey of the host-side management technologies of flash memory, application-/system-level flash-friendly designs, and emergent applications based on flash memory
Design and Optimization for AI/ML Acceleration on Resource-constrained and Edge Systems
No full textInternational audienceThe rapid advancement of AI (from foundational machine learning to Large Language Models) and edge computing has placed unprecedented demands on computation, memory, and storage on resource-constrained edge devices. As AI models scale, the ability to efficiently manage computing resources, utilize memory and storage, and reduce energy consumption has become critical. This paper introduces contributions on 4 topics related to deploying AI on resource-constrained edge devices: 1) unlocking training of foundational machine learning algorithms on the edge, 2) exploring hardware-aware DNN architecture and mapping co-optimization for inference on heterogeneous systems, 3) scaling RAG by leveraging advanced memory, storage, and energy-efficient designs, and 4) investigating cost-effective and high-performance large-scale graph processing
Training ML algorithms on resource-constrained devices — a memory/storage perspective
No full textInternational audienceDeploying ML/AI algorithms at the edge is essential for applications such as security and surveillance, industrial IoT, autonomous vehicles, and healthcare, which require low latency, data privacy, or reduced costs. However, most edge devices lack powerful memory systems capable of handling the memory- and computation-intensive nature of such applications.The objective of this presentation is to highlight some optimization strategies that help overcome the memory and storage bottlenecks of ML/AI algorithms—mainly from a training perspective—to enable their deployment on low-resource devices. These optimizations can also be applied to any resource-constrained environment used for training, including low-cost virtual machines in cloud infrastructures, standard personal computers, or small-scale micro data centers
Downstream tidal turbine transient local blade loading characterization
No full textInternational audienceFlow perturbations carried in the wake of an upstream turbine can have a significant impact on the local and transient loads observed on the downstream one. To get a better understanding of the effect of unsteady asymmetric flow on the load felt by a downstream turbine and develop a method to extract local and transient blade loading from CFD results, fully transient simulations designed to study this effect were performed with a RANS k-ω SST turbulence model using ANSYS-CFX. A horizontal axis tidal turbine (HATT) was used for the study. Three configurations were considered: the downstream turbine aligned with the upstream one, the downstream turbine offset by 0.5D and finally offset by 1D, with D being the diameter of the turbine. A 10D clearance between both turbines was used. Results show that when fully in-line, the downstream turbine sees reduction in power coefficient by almost 70 %, with a temporal variation of this coefficient having a relative amplitude of more than 30 %. Furthermore, the blades see localized loading varying by a factor of up to 2 during their rotation and the changes in the load amplitude applied at the same location are varying by more than 13 %. Blade load and flapwise bending moment display significant amplitude variations for the 0D and 0.5D offsets, with values 8 and 12 times higher to what is observed for the 1D offset
Peut-on jouer à concevoir des armes ?: Les 24 heures de l’innovation édition « Forces spéciales » comme hétérotopie
No full textInternational audienceIn the military context, designing weapons means creating equip-ment that is useful in combat. As this innovative work involves life-and-death issues, it is very particular in moral terms: ‘we innovate tokill’, said an officer interviewed during my inquiry. Based on my eth-nographic study of the 24h of Innovation, ‘Special Forces’ edition,I describe the conditions under which it becomes possible to initiateengineering students, most of whom are civilians, in the creation oftools of war – an activity with potentially lethal implications. By de-scribing the ‘framing’ and ‘coordination’ that support this innovationwork carried out jointly by engineering students and Special Forces,I show that this 24-hour programme takes on a heterotopic form inwhich all participants can end up playing at making weapons withoutfeeling any ethical qualms.Dans le cadre militaire, concevoir des armes revient à forger des équipements utiles au combat. Ce travail d’innovation emporte des enjeux de vie et de mort. Dès lors, il s’avère spécifique sur le plan moral : « on innove pour tuer » disait un officier interrogé au long de nos enquêtes. En réalisant l’ethnographie des 24heures de l’innovation édition Forces spéciales, nous décrirons alors à quelles conditions il devient possible d’initier des élèves-ingénieurs – majoritairement civils – à forger des outils de guerre et s’engager dans une activité aux implications potentiellement létales. En décrivant les opérations de « cadrage » et de « coordination » qui soutiennent ce travail d’innovation réalisé conjointement par des élèves-ingénieurs et des soldats des Forces spéciales, nous montrerons que ce dispositif en 24H prend une forme hétérotopique dans laquelle tout participant peut en venir à jouer à faire des armes sans ne ressentir de souffrances éthiques particulières
Differing and Unusual Orbits: Space Power Beyond the Vertical
No full textInternational audienceThis talk aimed to show that discourses on vertical power have a tendency to forget that objects in orbital space are not transcendental objects, but are themselves submitted to real relationships of force and fragility. Once this is taken into account, the very image and logic of power and politics over the course of the 20th century changes. One discovers that we were post-planetary before we were planetary, while the planetarization of discourse, which has gone together with a focalization on the vertical dimension of power, rather than thinking through the problem of being post-planetary to its conclusion, represses it
Spatial Innovations: Technological Sovereignty and the Reshaping of Geopolitics
No full textInternational audienceThis intervention analyzed contemporary and historical discussions of technological sovereignty. It argued that beyond the stated defensive aim of achieving technological independence, the quest for technological sovereignty is understood as an offensive form of national power. This is achieved through innovations that provide access to new political spaces like cyberspace and orbital space. The liberal technologies enabling this access facilitate novel forms of astro- and cyber-coloniality, usurping national agency while nominally respecting territorial borders. It shows that contemporary nation states find themselves confronted with a tragic conundrum: while pursuing technological autonomy reduces vulnerability, it forfeits influence and may be illusory. Conversely, engaging in the race for technological competition offers benefits but risks creating debilitating dependencies, exacerbating environmental crises on Earth and in space, and concentrating excessive power in private hands
Rethinking Theory
No full textInternational audienceThis intervention dealt with the limits of currently popular theories to deal with the problem of Earth-Space sustainability. It called for a rethinking of the planetary framework currently in fashion in the name of an Earth-Space approach which thinks the planet as well as local space. It also highlighted the ways in which the current paradigm actively contributes to exacerbating the problems generated by space junk by drawing attention back towards the terrain, and so stifling efforts to acquire new forms of Earth-Space literacy
Caractérisation de la rupture d'interfaces collées Titane/Composite sous chargement Dynamique Multiaxial
No full textInternational audienceCaractérisation de la rupture d'interfaces collées Titane/Composite sous chargement Dynamique Multiaxia