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ACES: generating diverse programming puzzles with autotelic language models and semantic descriptors
No full textInternational audienc
Estimating the Coverage Measure and the Area Explored by a Line-Sweep Sensor on the Plane
No full textThis paper presents a method for determining the area explored by a line-sweep sensor during an area-covering mission in a two-dimensional plane. Accurate knowledge of the explored area is crucial for various applications in robotics, such as mapping, surveillance, and coverage optimization. The proposed method leverages the concept of coverage measure of the environment and its relation to the topological degree in the plane, to estimate the extent of the explored region. In addition, we extend the approach to uncertain coverage measure values using interval analysis. This last contribution allows for a guaranteed characterization of the explored area, essential considering the often critical character of area-covering missions. Finally, this paper also proposes a novel algorithm for computing the topological degree in the 2-dimensional plane, for all the points inside an area of interest, which differs from existing solutions that compute the topological degree for single points. The applicability of the method is evaluated through a real-world experiment
High repetition rate relativistic laser–solid–plasma interaction platform featuring simultaneous particle and radiation detection
No full textInternational audienceWe report on a uniquely designed high repetition rate relativistic laser–solid–plasma interaction platform, featuring the first simultaneous measurement of emitted high-order harmonics, relativistic electrons, and low divergence proton beams. This versatile setup enables detailed parametric studies of the particle and radiation spatio-spectral beam properties under a wide range of controlled interaction conditions, such as pulse duration and plasma density gradient. Its array of complementary diagnostics unlocks the potential to unravel interdependencies among the observables and should aid in further understanding the complex collective dynamics at play during laser–plasma interactions and in optimizing the secondary beam properties for applications
Generative AI in the Classroom: Can Students Remain Active Learners?
No full textInternational audienceGenerative Artificial Intelligence (GAI) offers both great opportunities and challenges in education. On one hand, it may provide personalized and interactive pedagogical content that could favor students' intrinsic motivation and active engagement. This may empower them to have more control over their learning, and access diverse knowledge in diverse cultural backgrounds. On the other hand, GAI properties such as lack of uncertainty signalling, low reliability, and steerability could lead to opposite effects, e.g. over-estimation of one's own competencies, persistence in inadequate beliefs, passiveness, impaired curiosity and critical-thinking. These negative effects are amplified by the lack of a pedagogical stance in these models' behaviors. Indeed, as opposed to standard pedagogical activities, GAI systems are often designed to answers users' inquiries in ways that aim to please them, without asking to make efforts, and without considering their learning process.This article outlines some of these opportunities and challenges, with a focus on students' active learning strategies and related metacognitive skills when they use GAI in an educational context. To leverage opportunities and mitigate challenges, we present a framework introducing pedagogical transparency in GAI-based educational applications. This includes 1) methods for training models that consider pedagogical principles; 2) methods to ensure controlled and pedagogically-relevant interactions when designing activities with GAI, involving teachers and other stakeholders and 3) educational methods enabling students and teachers to acquire the relevant skills to properly benefit from the use of GAI in education (meta-cognitive skills, GAI literacy)
On cosmic injustices: Critical thinking, outer space, green values, and capitalist ideologies in a planetary age
No full textInternational audienceIt may seem obvious that the interests of social justice should always align with environmental justice on a limited planet Earth. Unfortunately, this is far from the case in practice, even in the Anthropocene. This essay provides a new cognitive mapping of how ideologically charged discourse splits the interests of people and planet. It offers a pragmatic, semantic, and spatial analysis of how arguments for planetary protection can infelicitously turn into justifications for broadening social inequalities (and the inverse). As such, it presents an implicit critique of holist theories. In striving to demonstrate the fundamental unity of society and the environemnt risk, holistic thinking leaves critics with an impoverished critical toolbox incapable of differentiating between transparently fraudulent greenwashing and scientifically supportable, but ideologically charged, claims. This text is focused on the spatial dimension of Anthropocene ideology. It places a particular focus on the growing place and rhetorical function of outer space within the Anthropocene economy. It illustrates that the promise of extraterrestrial growth, at least when this growth is contextualized against a zoned extraterrestrial space, has emerged as a potent means of justifying inequality in the name of planetary well-being, and so also of justifying the gospel of growth despite our increasing awareness of the limits of our planet
Heidegger’s Horror: Denken und Dichten at the Dawn of the Space Age
No full textInternational audienceIt re-reads the late Heidegger via an encounter with the dawn of the Space Age, and likewise rethinks space history, and so too Anthropocene history, in light of this encounter with Heidegger.The central claim of the paper is that Heidegger was much more influenced by Sputnik, Luna, and the other events which signified the dawning of what he called the "rocket age" than is typically believed. So influenced, in fact, that he claimed that this issued in a rupture in his thinking on technology, proclaiming that we no longer lived in the "atomic age" but in the "rocket age." Starting from this rupture, the paper sets out to trace the consequences of the rocket age not only on Heidegger's thinking about poetry and thinking in the late 1950's and 60's, but also in terms of his influence, and so the influence of space history, on the next generation of thinkers, in this case, Michel Foucault and Jacques Derrida.The essay is the first of a series of works attempting to rethink where we are, not only by looking at the planetization linked to the historical emergence of our extraterrestrial infrastructure, but at the resonances of this emergence on the ways in which we came to navigate and planetize inner space via experimental forms of thinking and writing
Diastereo-and Enantioselective Palladium-Catalyzed Cycloadditions of 5-Vinyloxazolidine-2,4-diones with Electrophilic Imines
No full textInternational audienceDespite the importance of the 4-imidazolidinone scaffold in bioactive compounds or organocatalysts, methodologies to access these nitrogenated heterocycles remain scarce. This manuscript describes a novel preparation of 4-imidazolidinones via a diastereo-and enantioselective (3+2) cycloaddition between 5-vinyloxazolidine-2,4-diones (VOxD) and electrophilic imines under palladium catalysis. This work supports the synthetic potential of VOxD as promising equivalents of the C-C(=O)-N synthon
Investigating Multi-tier and QoS-aware Caching based on ARC
No full textInternational audienceMemory caching is a common practice to reduce application latencies by buffering relevant data in high speed memory. When the volume of data to cache is too large or a DRAM-based solution too expensive, several technologies such as NVM or high speed SSDs could complement DRAM to form a multi-tier cache. Additionally, most existing policies focus on categorizing the data based on factors like recency and frequency, setting aside the fact that applications/customers have varying Quality-of-Service requirements. This concept is well established in Cloud environment with Service Level Agreement (SLA). In this paper, by extending the Adaptive Replacement Cache (ARC), that uses recency and frequency lists, we propose a QoSaware Multi-tier Adaptive Replacement Cache (QM-ARC) policy with the ability to take into account data applications/customers priorities through the concept of penalty borrowed from the Cloud. QM-ARC is generic, as it can be applied whatever the number of tiers and can accommodate different penalty functions. Using synthetic and real traces, our solution improved QoS as compared to state-of-the-art work
Coupling large-spatial scale larval dispersal modelling with barcoding to refine the amphi-Atlantic connectivity hypothesis in deep-sea seep mussels
No full textInternational audienceIn highly fragmented and relatively stable cold-seep ecosystems, species are expected to exhibit high migration rates and long-distance dispersal of long-lived pelagic larvae to maintain genetic integrity over their range. Accordingly, several species inhabiting cold seeps are widely distributed across the whole Atlantic Ocean, with low genetic divergence between metapopulations on both sides of the Atlantic Equatorial Belt (AEB, i.e. Barbados and African/European margins). Two hypotheses may explain such patterns: (i) the occurrence of present-day gene flow or (ii) incomplete lineage sorting due to large population sizes and low mutation rates. Here, we evaluated the first hypothesis using the cold seep mussels Gigantidas childressi, G. mauritanicus, Bathymodiolus heckerae and B. boomerang . We combined COI barcoding of 763 individuals with VIKING20X larval dispersal modelling at a large spatial scale not previously investigated. Population genetics supported the parallel evolution of Gigantidas and Bathymodiolus genera in the Atlantic Ocean and the occurrence of a 1-3 Million-year-old vicariance effect that isolated populations across the Caribbean Sea. Both population genetics and larval dispersal modelling suggested that contemporary gene flow and larval exchanges are possible across the AEB and the Caribbean Sea, although probably rare. When occurring, larval flow was eastward (AEB - only for B. boomerang ) or northward (Caribbean Sea - only for G. mauritanicus ). Caution is nevertheless required since we focused on only one mitochondrial gene, which may underestimate gene flow if a genetic barrier exists. Non-negligible genetic differentiation occurred between Barbados and African populations, so we could not discount the incomplete lineage sorting hypothesis. Larval dispersal modelling simulations supported the genetic findings along the American coast with high amounts of larval flow between the Gulf of Mexico (GoM) and the US Atlantic Margin, although the Blake Ridge population of B. heckerae appeared genetically differentiated. Overall, our results suggest that additional studies using nuclear genetic markers and population genomics approaches are needed to clarify the evolutionary history of the Atlantic bathymodioline mussels and to distinguish between ongoing and past processes