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Images et imaginaires du système autoroutier bordelais, en transition ?
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Building coercive Lyapunov–Krasovskii functionals based on Razumikhin and Halanay approaches
No full textInternational audienceIn this article, we provide a systematic and constructive way to build a Lyapunov–Krasovskii functional for time‐delay systems whose stability can be established through the Razumikhin or the Halanay approaches. The constructed Lyapunov–Krasovskii functional turns out to be coercive, meaning sandwiched between functions of the state history norm, and to dissipate in terms of the whole history norm. We present these results in the framework of input‐to‐state stability (ISS) in order to further account for the influence of input disturbances. A special emphasis is also given on exponential stability and exponential ISS. We illustrate our findings though the study of a coupled ODE‐PDE model of a chemical reactor, and show that, unlike most results in that area, our approach happens to ensure ISS in terms of the supremum norm of the state
Morse frames
No full textInternational audienceIn the context of discrete Morse theory, we introduce Morse frames, which are maps that associate a set of critical simplexes to all simplexes. The main example of Morse frames are the Morse references. In particular, these Morse references allow computing Morse complexes, an important tool for homology. We highlight the link between Morse references and gradient flows. We also propose a novel presentation of the Annotation algorithm for persistent cohomology, as a variant of a Morse frame. Finally, we propose another construction, that takes advantage of the Morse reference for computing the Betti numbers in mod 2 arithmetic
The impossibility of non-manipulable probability aggregation
No full textURL des Documents de travail : https://centredeconomiesorbonne.cnrs.fr/Documents de travail du Centre d'Economie de la Sorbonne 2024.01 - ISSN : 1955-611XA probability aggregation rule assigns to each profile of probability functions across a group of individuals (representing their individual probability assignments to some propositions) a collective probability function (representing the group's probability assignment). The rule is "non-manipulable" if no group member can manipulate the collective probability for any proposition in the direction of his or her own probability by misrepresenting his or her probability function ("strategic voting"). We show that, except in trivial cases, no probability aggregation rule satisfying two mild conditions (non-dictatorship and consensus preservation) is non-manipulable
The great expansion: The exceptional spread of bank branches in interwar France
No full textInternational audienceUsing newly collected data at the city level between 1910 and 1938, this article shows that, after World War I, France experienced an unprecedented expansion in bank branches mostly due to the creation of temporary branches in rural areas. The banking crisis in early 1930s paused this expansion. Nevertheless, the number of bank branches per capita remained four times higher than before the war. Also, the expansion of bank branches was not associated with an increase in the ratio of bank assets to national income. These findings re-evaluate the Great Reversal hypothesis in banking and reveal the disconnection between geographical expansion of banks and standard measures of financial development. Both trends can be reconciled if one considers that banks are multi-product firms-not just lenders-and that competition for new customers is not always associated with greater credit activity
Comprehensive analysis of a widely pharmaceutical, furosemide, and its degradation products in aquatic systems: Occurrence, fate, and ecotoxicity
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Researching infrastructures and cities: origins, debates, openings
No full textInternational audienceA number of scholars within the social sciences have remarked that we are in the midst of both an ‘infrastructural moment’ – with massive symbolic and financial investment in, especially, energy, digital and transport infrastructures – and an ‘infrastructural turn’ – with a growing and increasingly diverse use of the notion in various research areas (see, e.g., Amin, 2014; Howe et al., 2016; Harvey et al., 2016; Chatzis, 2017; Jarrige et al., 2018; Lawhon et al., 2018; Pike et al., 2019; Addie et al., 2020). 1 Indeed, infrastructures have been at the forefront of major and interrelated transformations for several decades, from the intensification of global environmental changes (such as climate change) and responses to these changes to the ongoing, multifaceted ‘digital transition’, through accelerated processes of urbanisation, and increased economic and metabolic2 globalisations. This context has fuelled a renewed interest in infrastructures in public and academic debates.This Handbook of Infrastructures and Cities reflects and builds on this context
Impact of socioeconomic determinants on the speed of epidemic diseases: a comparative analysis
No full textInternational audienceWe study the impact of socioeconomic factors on two key parameters of epidemic dynamics. Specifically, we investigate a parameter capturing the rate of deceleration at the very start of an epidemic, and a parameter that reflects the pre-peak and post-peak dynamics at the turning point of an epidemic like coronavirus disease 2019 (COVID-19). We find two important results. The policies to fight COVID-19 (such as social distancing and containment) have been effective in reducing the overall number of new infections, because they influence not only the epidemic peaks, but also the speed of spread of the disease in its early stages. The second important result of our research concerns the role of healthcare infrastructure. They are just as effective as anti-COVID policies, not only in preventing an epidemic from spreading too quickly at the outset, but also in creating the desired dynamic around peaks: slow spreading, then rapid disappearance
Condition mobile. Ressorts de l'imaginaire
No full textInternational audienceQue fait la mobilité aux mondes urbains ? Infrastructures, architectures, technologies, images, pratiques : pour qui s’intéresse aux futurs des villes, à leurs passés et leurs présents, l’imaginaire constitue un champ fécond de compréhension. En scrutant les objets, les langages, les dispositifs, et leurs multiples apparitions, Anne Jarrigeon et Nathalie Roseau explorent, à travers l’imaginaire, l’un des ressorts les plus puissants de l’expérience contemporaine, l’une de ses inséparables conditions : la mobilité. Livre à deux voix, Condition mobile croise les temporalités et les disciplines : l’ethnologie urbaine, l’anthropologie visuelle et la sémiotique pour Anne Jarrigeon, l’architecture, l’aménagement du territoire et l’histoire pour Nathalie Roseau