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The Gamification of Society
No full textInternational audienceThe applications of gamification and the contexts in which game elements can be successfully incorporated have grown significantly over the years. They now include the fields of health, education, work, the media and many others. However, the human and social sciences still neglect the analysis and critique of gamification. Research conducted in this area tends to focus on game objects and not gamification’s logic as its ideological dimension.Considering that the game, as a model and a reference, laden with social value, deserves to be questioned beyond its objects, The Gamification of Society gathers together texts, observations and criticisms that question the influence that games and their “mechanics” have on wider society. The empirical research presented in this book (examining designers’ practices, early childhood, political action, the quantified self, etc.) also probes several different national contexts – those of Norway, Belgium, the United States and France, among others
Uncanny Simulacra: Pedagogy and Student Artwork as Tools for Interrogating Post-human Worlds
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Homo Stellaris and the Uncommon Commons: Who Should be the Subject of the Post-Planetary Future?
No full textInternational audienceIs there a subject of the post-planetary future? Will there be a post-planetary future? Is this not merely a question for science fiction, even a science fictional question? Such questions and doubts are justified, and the following undoubtedly has much in common with what Donna Haraway (2016, p. 10) has called "speculative fabulation:" it is a myth of two "string figures," two conceptual personae, two different ways of being a player in an anticipated post-planetary world, two ways of thinking about how science fact, speculative fabulation, science fantasy, and so forth might come together as humankind-or more properly-posthumankind-becomes post-planetary, spreading out beyond the Earth and into the solar system. That said, and herein lies the rub, the question that concerns us it to a certain sense not speculative at all, nor is it one that needs to await its time, to be confronted only after we have concerned ourselves with the crisis of the present, call it what you will-the Anthropocene, the Capitolocene, or the Plantationocene. This is quite simply because all of these-cenes, all of these ways of organizing technosocial nature/cultures in the present are already post-planetary
Les défis environnementaux: un facteur de motivation pour devenir ingénieur ? Une enquête auprès des élèves-ingénieurs en Algérie, au Maroc et en Tunisie
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Robust structured H2 synthesis for linear systems subject to time-invariant uncertainties with global optimization
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Direct Adaptive Pole-Placement Controller using Deep Reinforcement Learning: Application to AUV Control
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Efficient Leader Election in Wireless Sensor and IoT Networks
No full textInternational audienceLeader Election is a classical problem in distributed systems in which one of the processes is chosen to organize a common task. In wireless sensor networks a leader is often a node of minimum or maximum value such as its identifier, remaining battery life, level of trust or its x- or y- coordinate in the plane which allows to start an algorithm to find the network’s boundary. We present and discuss the Dominating Tree Routing algorithm (DoTRo) which starts from local leaders, running as a root, the process of flooding (distributed BFS) to determine a spanning tree of the underlying graph. During this process, the value of the local leader will be routed and if two trees meet, the tree routing the better value will continue its process while the other one will stop. The root of the final spanning tree will be the leader of the network. We conclude with a performance evaluation and some applications
EMSx: a numerical benchmark for energy management systems
No full textInternational audienceInserting renewable energy in the electric grid in a decentralized manneris a key challenge of the energy transition. However, at local scale, both production and demand display erratic behavior, which makes it delicate to match them. It is the goal of Energy Management Systems (EMS) to achieve such balance at least cost. We present EMSx, a numerical benchmark for testing control algorithms for the management of electric microgrids equipped with a photovoltaic unit and an energy storage system. EMSx is made of three key components: the EMSx dataset, provided by Schneider Electric, contains a diverse pool of realistic microgrids with a rich collection of historical observations and forecasts; the EMSx mathematical framework is an explicit description of the assessment of electric microgrid control techniques and algorithms; the EMSx software EMSx.jl is a package, implemented in the Julia language, which enables to easily implement a microgrid controller and to test it. All components of the benchmark are publicly available, so that other researchers willing to test controllers on EMSx may reproduce experiments easily. Eventually, we showcase the results of standard microgrid control methods, including Model Predictive Control, Open Loop Feedback Control and Stochastic Dynamic Programming
Predicting file lifetimes for data placement in multi-tiered storage systems for HPC
No full textInternational audienceThe emergence of Exascale machines in HPC will have the foreseen consequence of putting more pressure on the storage systems in place, not only in terms of capacity but also bandwidth and latency. With limited budget we cannot imagine using only storage class memory, which leads to the use of a heterogeneous tiered storage hierarchy. In order to make the most efficient use of the high performance tier in this storage hierarchy, we need to be able to place user data on the right tier and at the right time. In this paper, we assume a 2-tier storage hierarchy with a high performance tier and a high capacity archival tier. Files are placed on the high performance tier at creation time and moved to capacity tier once their lifetime expires (that is once they are no more accessed). The main contribution of this paper lies in the design of a file lifetime prediction model solely based on its path based on the use of Convolutional Neural Network. Results show that our solution strikes a good trade-off between accuracy and under-estimation. Compared to previous work, our model made it possible to reach an accuracy close to previous work (around 98.60% compared to 98.84%) while reducing the underestimations by almost 10x to reach 2.21% (compared to 21.86%). The reduction in underestimations is crucial as it avoids misplacing files in the capacity tier while they are still in use
IWV retrieval from ship-borne GNSS receiver in the framework of the MAP-IO project
No full textInternational audience<p>In the framework of the research project &#8220;Marion Dufresne Atmospheric Program &#8211; Indian Ocean&#8221; (MAP-IO), which is aiming at collecting long-term atmospheric and marine biology observations in the under-instrumented Indian and Austral Oceans, a Global Navigation Satellite System (GNSS) receiver was installed on the research vessel (RV) Marion Dufresne in October 2020 to describe, and monitor, global moisture changes in these areas. GNSS raw data are recorded continuously and used to retrieve integrated water vapor contents (IWV) along the RV route.</p><p>After a data quality check that confirmed that a wise choice of location of the GNSS antenna on the RV is crucial to avoid mask, signal reflection and interference from other instruments that may degrade IWV retrieval, a first assessment of the GNSS analysis performances was carried out by comparing the vertical component of the estimated positions to sea surface height model. The differences are on the order of 20 to 30 cm; they are consistent with both the error budget for sea surface height determination using GNSS and the sea surface height model formal errors.</p><p>An evaluation of GNSS-derived IWV was conducted using IWV estimates from the ECMWF fifth ReAnalysis (ERA5) and ground-based GNSS reference stations located nearby the tracks of RV Marion Dufresne. Preliminary analyses show encouraging results with a mean root mean square error of ~2-3&#160;kg&#160;m<sup>-</sup><sup>2</sup> between ERA5 and GNSS-derived IWV. The use of ultra-rapid GNSS orbit and clock product was also investigated to assess the performance of near real-time GNSS-derived IWV estimation for numerical weather prediction purposes.</p>