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JOSEPH FORD: THE EVANGELIST OF (HAMILTONIAN) CHAOS
No full textInternational audienceThis chapter is devoted to Joseph Ford’s contribution to the development of chaos theory and, more specifically, to the branches we can call conservative (more largely, Hamiltonian chaos) chaos and quantum chaos, the latter being a subclass of the former. Here, Ford reveals himself to be a man of insatiable generosity and boundless altruism. His energy was spent for the benefit of the chaos community, leading to the dissemination of over 1000 abstracts between 1978 and 1980, up to the creation of Physica D. He was the privileged interlocutor of Boris Chirikov, and a close friend of Otto E. Rössler
Climate change and resilience in the agricultural sector: The case of the impact of COVID-19 in the French wine industry
No full textInternational audienceThis chapter examines the impact of climate change and the COVID-19 pandemic on the French wine industry, focusing on governance and resilience across various actors in the wine value chain. Using a mixed-methods approach, it explores how institutional frameworks and organizational structures influence firms’ capacity to adapt to external shocks. The study highlights differences in resilience among cooperatives, independent winegrowers, and other industry players, emphasizing the importance of collaborative governance and strategic adaptation for sustaining the sector amid ongoing global challenges
Determining the optimal operating conditions of SOFCs electrolytes based on evolution of their electronic transport number with temperature and oxygen partial pressure: A case study of the Ce0.9Gd0.1O2-δ electrolyte
No full textInternational audienceOptimizing the performance of Solid Oxide Fuel Cells (SOFCs) or Solid Oxide Electrolysis Cells (SOECs) necessitates a thorough understanding of the electrolytes' transport properties under the device's operating conditions, whether through experimental data or established transport laws. This study investigates the electrical properties of Gd-doped ceria as a potential electrolyte material for SOFC applications. The electrical behavior of Gd-doped ceria was analyzed over a broad range of oxygen partial pressures (from 10−36 to 1 bar) and temperatures (200 °C to 900 °C) to establish the Patterson diagram, i.e., the variation of the total electrical conductivity as a function of the oxygen partial pressure (on logarithmic scales) for various temperatures. Additionally, the average transport number of the Gd-doped ceria electrolyte was evaluated under varying oxygen partial pressure gradients and temperatures using a specific semi-permeation method and compared with data derived from the Patterson diagram. The results collected in this study indicate that the use of Gd-doped ceria as an SOFC electrolyte requires precise control of oxygen partial pressure (particularly below 10−24 bar at 600 °C) or the hydrogen-to-water ratio at the hydrogen electrode to prevent efficiency degradation of the electrochemical system and to determine optimal operating conditions.</p
Discipline du corps, formation d’un esprit : approche sur la socialisation scolaire à partir du roman l’Athénée, de Raul Pompeia (1863-1895)
No full textInternational audienceCet article propose une analyse sociologique des mécanismes disciplinaires décrits dans l’Athénée, roman de l’écrivain brésilien Raul Pompeia. La représentation de l’Athénée comme une école, c'est-à-dire comme un lieu de production et de préservation de rites, de croyances et de techniques produisant un effet souhaité de disciplinement, suggère, dans cette analyse, une possible articulation entre les concepts de pouvoir symbolique de Bourdieu et de pouvoir disciplinaire de Foucault appliqués au quotidien scolaire. Ainsi, les technologies disciplinaires ordinairement associées à l'espace éducatif sont examinées, en abordant les positions des agents impliqués dans la routine disciplinaire de l’Athénée à travers des dispositions, des intérêts et des significations collectivement construits
Differential Taphonomic Behavior of Flint Types: Experimental Insights and Implications for the Middle Stone Age Assemblages of Wadi Lazalim in the Northern Sahara (Kebili, Tunisia)
No full textInternational audienceSeveral syn and post-depositional processes are responsible for different degrees of site and assemblage formation and disturbance. Understanding the processes that lead to archaeological site formation is essential for interpreting past human activities, settlement patterns, and occupation dynamics. Among these processes, water flow is commonly recognized as a major factor influencing site and assemblage formation and integrity. Lithic taphonomy can add valuable information to the understanding of these natural processes. To better evaluate how different flint types react to both mechanical and chemical stresses, we carried out controlled and sequential experiments on knapped flint artifact replicas. These were realized on two different flint varieties, recognized in the archaeological assemblage of a Middle Stone Age open-air site located at Wadi Lazalim (Southern Tunisia). Our methodological framework is based on a sequential tumbling experiment that simulates the remobilization of artifacts by water. The resulting post-depositional surface modifications (PDSM) were observed and recorded. In addition, a sample of flint replicas underwent chemical alteration in a controlled environment, allowing us to document and measure both patina formation and changes in surface roughness. These experimental results were then compared with a sample of archaeological materials, providing the basis for a preliminary and exploratory hypothesis concerning the taphonomic processes at the site. Here, we observed that most of the alterations appear to be linked to patina formation, whose variable degree and kind are more strongly correlated with differences in raw material texture rather than to the co-occurrence of artefacts from different chronological spans
Adaptive Model Selection using Meta Models and Drift Adaptation
No full textInternational audienceSmart spaces that have deployed machine learning (ML) models for intelligent decision typically evolve over time. Model selection is a key step in deploying (ML) models, particularly in dynamic environments where data distribution shifts can impact model accuracy over time. Existing approaches often rely on evaluating many candidate models against predefined metrics, which is computationally expensive and neither suitable for real-time applications nor dynamic environments. This paper presents an adaptive model selection technique that combines meta-modeling with drift detection to improve efficiency and robustness. Meta-models are used to evaluate the suitability of candidate models under different constraints, such as predictive accuracy and computational cost, without requiring full evaluation on the target data. This reduces the overhead of model selection while preserving deployment quality. In addition, a drift detection mechanism monitors changes in the data distribution and updates the selection strategy accordingly. The proposed approach contributes to automated machine learning (AutoML) by enabling adaptive, efficient, and reliable model selection in real-time environments
Judith Gautier’s Livre de Jade: Chinese Poetry in Mutation
No full textInternational audienceIn 1867, Judith Gautier published Le Livre de Jade, the first literary translation of Chinese poetry in the West – a work that achieved remarkable success during the Belle Époque. This success can be explained, in part, by the linguistic, cultural, and poetic mutations that Chinese poetry underwent through Gautier’s adaptation. The daughter of Théophile Gautier, she drew inspiration as much from Romanticism and the Parnassian movement as from classical Chinese poetry . This paper proposes to examine the Parnassian and Romantic mutations that intertwine in Le Livre de Jade, generating a profound aesthetic renewal.We will also explore the various strategies employed by Judith Gautier to Westernise Chinese poetry, whether through the adaptation of vocabulary or through intertextual references. Particular attention will be paid to the mutations of symbols drawn from Chinese poetry, which under Gautier’s pen often become images devoid of their original symbolic depth. By avoiding footnotes in order to preserve a smooth reading experience for her French audience, the poet converts Chinese place names, fauna, and flora, thus offering the Belle Époque public a poetic vision of China. These mutations ultimately allowed Gautier to reinvent the poetic aesthetics of the Belle Époque through a freer poetic form, one that borders on prose poetry: we will therefore observe that Le Livre de Jade was appreciated less as a translation than as an original work of poetry, exerting a notable influence on Belle Époque poets, especially within the Symbolist movement.Situated at the crossroads of French literature, comparative literature, and translation studies, this proposal offers a new perspective on Le Livre de Jade as a pioneering work of cultural transfer between China and France, viewed through the prism of aesthetic and cultural mutation
Comparison of silver zeolites of natural and synthetic origins on their ability to trap irreversibly CH<sub>3</sub>I in conditions representative of severe nuclear accident
No full textInternational audienceIn the present work, a low-cost silver natural zeolite (AgN) with clinoptilolite structure and ≈ 9 wt% Ag was specifically designed and evaluated for the capture of methyl iodide (CH3I) in a range of conditions representative of severe nuclear accident (T = 80-140°C, high steam contents, presence of CO, γ-irradiation….). The physicochemical and textural characteristics of AgN were first characterized by SEM-EDX, DR-UV-Visible spectroscopy, N2 porosimetry, elemental analysis and compared to those of well-known synthetic silver faujasite zeolites (AgX and AgY). Common features and differences existing between AgY and AgN in terms of CH3I trapping mechanism were addressed by FTIR spectroscopy and DRIFTS. CH3I adsorption capacities were also computed from CH3I breakthrough curves measured in absence/presence of pre-adsorbed water. Interestingly, the CH3I trapping efficiencies measured at 140°C were found to strongly depend on the type of silver zeolite and steam content. Up to a water content of 42 wt% in the feed, both AgN sorbent and synthetic exchanged faujasites AgX and AgY performed very well, with decontamination factors in the range 5.105-103. At higher humidity (45 wt%), the filling of pores by liquid water induced a rather drastic drop in measured DF values, which is less pronounced for AgY. Additional challenging tests (presence of CO, trapping stability under γ-irradiation) have confirmed the potential of tailored silver zeolites for effective CH3I retention in severe accident scenarios