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A Rainbow in Deep Network Black Boxes
No full textInternational audienceA central question in deep learning is to understand the functions learned by deep networks. What is their approximation class? Do the learned weights and representations depend on initialization? Previous empirical work has evidenced that kernels defined by network activations are similar across initializations. For shallow networks, this has been theoretically studied with random feature models, but an extension to deep networks has remained elusive. Here, we provide a deep extension of such random feature models, which we call the rainbow model. We prove that rainbow networks define deterministic (hierarchical) kernels in the infinite-width limit. The resulting functions thus belong to a data-dependent RKHS which does not depend on the weight randomness. We also verify numerically our modeling assumptions on deep CNNs trained on image classification tasks, and show that the trained networks approximately satisfy the rainbow hypothesis. In particular, rainbow networks sampled from the corresponding random feature model achieve similar performance as the trained networks. Our results highlight the central role played by the covariances of network weights at each layer, which are observed to be low-rank as a result of feature learning
Excited States in the Neutron Rich Nuclei S and S
No full textInternational audienceData on the structure of sulphur isotopes close to the neutron drip-line are rather scarce. The excited states of the very neutron-rich S and S nuclei have been investigated by in-beam gamma-ray spectroscopy at the Radioactive Isotope Beam Factory at the RIKEN Nishina Center. After multi-nucleon knockout reactions on the liquid-hydrogen MINOS target, the gamma transition of S, already reported in literature, has been confirmed. Additionally, two new gamma rays have been assigned to this isotope and one gamma line has been observed in S
L’écho de la conversion à la foi latine de l’empereur byzantin Jean V Palaiologos (1369) : le témoignage de la Vie de Makarios par Philothéos de Sélymbria
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ARCHIBAB 5 : « Écoute ma tablette ! » L'essor de la correspondance en Mésopotamie (2004–1595 av. n. è.)
No full textInternational audienceIn Mesopotamia, writing was invented and long mastered by a small group of individuals in service to the palace and temples. Archaeological and epigraphic evidence attests to an intensification and broadening use of writing in the first half of the second millennium BC, during the so-called Old Babylonian or Amorite period (2004–1595). The exchange of letters became so commonplace that scribes of that era considered writing to have been invented for remote communication. This book explores the rise of correspondence during this period. The first chapter contextualizes the letters, written in Akkadian at the time, within their social framework by profiling the individuals who corresponded in writing. The second chapter highlights, among the scribal exercises studied during the curriculum, those that taught reading and writing letters in Akkadian. The practice letters copied in school, in particular, are examined in detail for the first time. The third chapter focuses on the content of letters throughout the centuries, while the fourth chapter draws inspiration from pragmatics and textual linguistics to compare the degree of implicitness and complexity in around three hundred letters written between the 20th and 17th centuries. This research not only offers a pioneering synthesis of knowledge gathered over the past 130 years on a corpus of over 7,000 Old Babylonian letters but also provides a fresh and innovative exploration into the context, content, and language of these letters.En Mésopotamie, l’écriture fut inventée et longtemps maîtrisée par un groupe restreint d’individus au service du palais et des temples. Les données archéologiques et épigraphiques témoignent d’une intensification et d’une généralisation du recours à l’écrit dans la première moitié du deuxième millénaire avant notre ère, pendant la période dite paléo-babylonienne ou amorrite (2004–1595). Il était alors devenu si courant d’envoyer des lettres que les scribes de cette époque considéraient que l'écriture avait été inventée pour communiquer à distance. Ce livre étudie l'essor de la correspondance pendant cette période. Le premier chapitre replace les lettres, qui sont en langue akkadienne, dans leur contexte social en dressant le portrait des individus qui correspondaient par écrit. Le second chapitre présente, parmi les exercices étudiés pendant le cursus scribal, ceux qui permettaient d'apprendre à lire et à écrire des lettres en akkadien. Celles copiées à l'école, en particulier, sont étudiées en détail pour la première fois. Le troisième chapitre est dédié au contenu des lettres à travers les siècles tandis que le quatrième chapitre s'inspire de la pragmatique et de la linguistique textuelle pour comparer le degré d'implicite et la complexité d'environ trois cents lettres rédigées entre le XXe et le XVIIe siècles. Cette recherche offre pour la première fois une synthèse des connaissances accumulées au cours des 130 dernières années autour d'un corpus constitué de plus de 7000 lettres paléo-babyloniennes et explore de manière innovante le contexte, le contenu et la langue de ces textes
Fouilles archéologiques et prospections à Caričin Grad (Justiniana Prima) en Serbie. Campagne 2023 [notice archéologique], Bulletin archéologique des Écoles françaises à l’étranger
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The Making of an Attractive Guidebook: The Case of the “Illustrated Collection of Famous Things from the Mountains and Seas of Japan” (1754)
No full textInternational audienceAmong the books printed in Japan during the Edo period (1603–1868), the category of popular guides or encyclopedias enjoyed enormous success from the outset. Diverse and constantly enriched to meet the public’s expectations, these works were designed to introduce commoners to fields of knowledge previously available only to connoisseurs. The work entitled “Illustrated Collection of Famous Things from the Mountains and Seas of Japan” (Nippon sankai meibutsu zue, hereafter Meibutsu zue) is not strictly speaking an encyclopedia. The author’s aim was not so much to compile an exhaustive inventory of the “famous things” (meibutsu) that filled Ōsaka’s markets, but rather to educate the public about the conditions under which they were produced. The book reflects the economic development of rural Japan, where farmers were increasingly concerned with marketing and selling their products in towns. The Meibutsu zue focuses on images of the production sites. Each entry consists of a large illustration covering almost two pages, with a few lines of commentary explaining production methods.The paper examines the different formats and uses of images in earlier popular encyclopedias while also comparing the Meibutsu zue to other works that describe or depict various production process for rural products. By tracing the genesis of Meibutsu zue in this fashion, my aim is to highlight the innovative nature of the work
蛍の巻の物語論の再検討を目指して
No full textInternational audienceCette étude examine quelques lectures proposées jusqu'ici du "débat sur les romans" du chapitre des Lucioles et proposent de le relire en le replaçant dans l'économie générale du Roman du Genji
Byzance dans la photographie patrimoniale au XIXe siècle : le fonds Charles Labbé.
No full textIn 1853, a French painter, Charles Labbé (dead in 1885) and a French engineer and photographer, Ernest de Caranza (dead in 1868) went to a photographic mission to Mont Athos, at the Abdülmecit sultan's first request. It is the artistic legacy of this mission, an unprecedented album of 89 photographs that this thesis highlights and proposes to analyze in its historical context.The photographic mission of Charles Labbé and Ernest de Caranza allows the creation of a photographic album of exceptional technical quality for this period. This red Morocco photographic album contains 87 salt prints, that are the oldest photographs known of Mont Athos. Remaining in the family of Charles Labbé, the album was sold at Sotheby's in Paris in November 2016, becoming a rare object. It offers an unprecedented documentation space for researchers, showing the state of these monuments and their evolution, but also the important dimension of Byzantine art in France.Mont Athos, in the 19e century, under ottoman domination, is the purest expression of the Byzantine Art for westerners. French artists, writers and first scholars are fascinated about Roman, Gothic and Byzantine Art, that some people see everywhere. The Victor Hugo ‘s novel, entitled Notre-Dame de Paris, published in 1831, and the Viollet-le-Duc's restorations are the symbols of this passion.The work of the two French is in the wake of scholars and artists who discover the monastic island outside time like Dominique Papety one of the first to testify to his journey in a crucial article published in the Revue des Deux Mondes in 1846, showing the importance of Athonite heritage. In the 1850s, photography became, by its precision, a means of representation and documentation of Byzantine art. Photography became, in the 1850s, by its accuracy, a staple medium of representation, documentation and expression of the Byzantine art.Abdülmecit sultan the first's emblem drawn on the front cover shows that it is an Ottoman order. This photographic album might be a diplomatic gift for Napoleon III and Alexander II Tsar of Russia, which for obscure reasons they do not receive.This photographic collection paves the way to other photographic missions as ten years later the scholar Emmanuel Miller's mission, with the Young painter and photographer Pierre-Désiré Guillemet, or at the end of nineteenth century, Gabriel Millet. Photography, born in nineteenth century, is at the center of the Byzantian world, by the exceptional prism that it gives at researcher in the study of the architectural evolution of Mont Athos.En 1853, un peintre français, Charles Labbé (mort en 1885) et un ingénieur et photographe français, Ernest de Caranza (mort en 1868) partent en mission photographique au Mont Athos, à la demande du sultan Abdülmecit Ier. C'est l'héritage artistique de cette mission, un ensemble inédit d'épreuves photographique que cette thèse met en lumière et propose d'analyser dans son contexte historique. La mission photographique de Charles Labbé et Ernest de Caranza permet ainsi la création d'un album photographique d'une qualité technique exceptionnelle pour cette époque. Cet album photographique relié de marocain rouge contient 87 épreuves sur papier salé, qui sont les plus anciennes photographies connues du Mont Athos. Resté dans la famille de Charles Labbé, l'album a été vendu chez Sotheby's à Paris en novembre 2016, devenant un objet rare. Il offre un espace de documentation sans précédent pour les chercheurs, montrant l'état de ces monuments et leur évolution, mais aussi la dimension importante de l'art byzantin en France. Au XIXe siècle, le Mont Athos, sous domination ottomane, est l'expression la plus pure de l'art byzantin pour les occidentaux. Artistes, écrivains et premiers érudits français sont fascinés par l'art roman, gothique et byzantin, que certains voient partout. Le roman de Victor Hugo, Notre-Dame de Paris, publié en 1831, et les restaurations de Viollet-le-Duc sont les symboles de cette passion. L'œuvre des deux français se situe dans le sillage des érudits et artistes qui découvrent l'île monastique en dehors du temps à l'instar de Dominique Papety un des premiers à témoigner de son voyage dans un article crucial publié dans la Revue des Deux Mondes en 1846, montrant l'importance du patrimoine athonite. Dans les années 1850, la photographie est devenue, par sa précision, un moyen de représentation et de documentation de l'art byzantin. Le tuğra du sultan Abdülmecit Ier présent sur la couverture de montre qu'il s'agit d'une mission ottomane. Cet album photographique fut peut-être un cadeau diplomatique pour Napoléon III et le Tsar Alexandre II de Russie, que pour d'obscures raisons ils n'auraient pas reçu. Cette collection photographique ouvre la voie à d'autres missions photographiques comme dix ans plus tard la mission du savant Emmanuel Miller, accompagné du jeune peintre et photographe Pierre-Désiré Guillemet, ou à la fin du XIXe siècle, Gabriel Millet. La photographie, née au XIXe siècle, est au centre du monde byzantin, par le prisme exceptionnel qu'elle donne aux chercheurs dans l'étude de l'évolution architecturale du Mont Athos