Episciences.org
Not a member yet
6707 research outputs found
Sort by
Bivariate Chromatic Polynomials of Mixed Graphs
No full textThe bivariate chromatic polynomial of a graph ,introduced by Dohmen-P\"{o}nitz-Tittmann (2003), counts all -colorings of such that adjacent vertices get different colors if they are . Weextend this notion to mixed graphs, which have both directed and undirectededges. Our main result is a decomposition formula which expresses as a sum of bivariate order polynomials (Beck-Farahmand-Karunaratne-Zuniga Ruiz2020), and a combinatorial reciprocity theorem for .Comment: 10 pages, 3 figures, To appear in DMTCS vol.25:2 #2 (2023
A Theory of Formal Choreographic Languages
No full textWe introduce a meta-model based on formal languages, dubbed formalchoreographic languages, to study message-passing systems. Our framework allowsus to generalise standard constructions from the literature and to comparethem. In particular, we consider notions such as global view, local view, andprojections from the former to the latter. The correctness of local viewsprojected from global views is characterised in terms of a closure property. Weconsider a number of communication properties -- such as (dead)lock-freedom --and give conditions on formal choreographic languages to guarantee them.Finally, we show how formal choreographic languages can capture existingformalisms; specifically we consider communicating finite-state machines,choreography automata, and multiparty session types. Notably, formalchoreographic languages, differently from most approaches in the literature,can naturally model systems exhibiting non-regular behaviour
The Fractality of Sentiment Arcs for Literary Quality Assessment: the Case of Nobel Laureates
No full textIn the few works that have used NLP to study literary quality, sentiment and emotion analysis have often been considered valuable sources of information. At the same time, the idea that the nature and polarity of the sentiments expressed by a novel might have something to do with its perceived quality seems limited at best. In this paper, we argue that the fractality of narratives, specifically the longterm memory of their sentiment arcs, rather than their simple shape or average valence, might play an important role in the perception of literary quality by a human audience. In particular, we argue that such measure can help distinguish Nobel-winning writers from control groups in a recent corpus of English language novels. To test this hypothesis, we present the results from two studies: (i) a probability distribution test, where we compute the probability of seeing a title from a Nobel laureate at different levels of arc fractality; (ii) a classification test, where we use several machine learning algorithms to measure the predictive power of both sentiment arcs and their fractality measure. Lastly, we perform another experiment to examine whether arc fractality may be used to distinguish more or less popular works within the Nobel canon itself, looking at the probability of higher GoodReads’ ratings at different levels of arc fractality. Our findings seem to indicate that despite the competitive and complex nature of the task, the populations of Nobel and non-Nobel laureates seem to behave differently and can to some extent be told apart by a classifier. Moreover, the probability of Nobel titles having better ratings appears higher at different levels of arc fractality
Capturing the polynomial hierarchy by second-order revised Krom logic
No full textWe study the expressive power and complexity of second-order revised Kromlogic (SO-KROM). On ordered finite structures, we show that itsexistential fragment -KROM equals -KROM, andcaptures NL. On all finite structures, for , we show that equals -KROM if is even, and equals -KROM if is odd. The result gives an alternativelogic to capture the polynomial hierarchy. We also introduce an extendedversion of second-order Krom logic (SO-EKROM). On ordered finite structures, weprove that SO-EKROM collapses to -EKROM and equals . BothSO-EKROM and -EKROM capture co-NP on ordered finite structures
Generic HTR Models for Medieval Manuscripts. The CREMMALab Project
No full textIn the Humanities, the emergence of digital methods has opened up research questions to quantitative analysis. This is why HTR technology is increasingly involved in humanities research projects following precursors such as the Himanis project. However, many research teams have limited resources, either financially or in terms of their expertise in artificial intelligence. It may therefore be difficult to integrate handwritten text recognition into their project pipeline if they need to train a model or to create data from scratch. The goal here is not to explain how to build or improve a new HTR engine, nor to find a way to automatically align a preexisting corpus with an image to quickly create ground truths for training. This paper aims to help humanists easily develop an HTR model for medieval manuscripts, create and gather training data by knowing the issues underlying their choices. The objective is also to show the importance of the constitution of consistent data as a prerequisite to allow their gathering and to train efficient HTR models. We will present an overview of our work and experiment in the CREMMALab project (2021-2022), showing first how we ensure the consistency of the data and then how we have developed a generic model for medieval French manuscripts from the 13 th to the 15 th century, ready to be shared (more than 94% accuracy) and/or fine-tuned by other projects
Reduced-order modeling of geometrically nonlinear rotating structures using the direct parametrisation of invariant manifolds
No full textThe direct parametrisation method for invariant manifolds is a nonlinear reduction technique which derives nonlinear mappings and reduced-order dynamics that describe the evolution of dynamical systems along a low-dimensional invariant-based span of the phase space. It can be directly applied to finite element problems. When the development is performed using an arbitrary order asymptotic expansion, it provides an efficient reduced-order modeling strategy for geometrically nonlinear structures. It is here applied to the case of rotating structures featuring centrifugal effect. A rotating cantilever beam with large amplitude vibrations is first selected in order to highlight the main features of the method. Numerical results show that the method provides accurate reduced-order models (ROMs) for any rotation speed and vibration amplitude of interest with a single master mode, thus offering remarkable reduction in the computational burden. The hardening/softening transition of the fundamental flexural mode with increasing rotation speed is then investigated in detail and a ROM parametrised with respect to rotation speed and forcing frequencies is detailed. The method is then applied to a twisted plate model representative of a fan blade, showing how the technique can handle more complex structures. Hardening/softening transition is also investigated as well as interpolation of ROMs, highlighting the efficacy of the method
Universal quadratic forms and indecomposables in number fields: A survey
No full textWe give an overview of universal quadratic forms and lattices, focusing onthe recent developments over the rings of integers in totally real numberfields. In particular, we discuss indecomposable algebraic integers as one ofthe main tools.Comment: 34 pages, journal versio
Curve counting and S-duality
No full textWe work on a projective threefold which satisfies the Bogomolov-Giesekerconjecture of Bayer-Macr\`i-Toda, such as or the quinticthreefold. We prove certain moduli spaces of 2-dimensional torsion sheaves on aresmooth bundles over Hilbert schemes of ideal sheaves of curves and points in. When is Calabi-Yau this gives a simple wall crossing formula expressingcurve counts (and so ultimately Gromov-Witten invariants) in terms of counts ofD4-D2-D0 branes. These latter invariants are predicted to have modularproperties which we discuss from the point of view of S-duality andNoether-Lefschetz theory.Comment: Referee's corrections implemented; journal version. 25 pages, 4 figure
Lowerbounds for Bisimulation by Partition Refinement
No full textWe provide time lower bounds for sequential and parallel algorithms decidingbisimulation on labeled transition systems that use partition refinement. Forsequential algorithms this is and for parallel algorithms this is , where is the number of states and is the number of transitions. The lowerboundsare obtained by analysing families of deterministic transition systems,ultimately with two actions in the sequential case, and one action for parallelalgorithms. For deterministic transition systems with one action, bisimilaritycan be decided sequentially with fundamentally different techniques thanpartition refinement. In particular, Paige, Tarjan, and Bonic give a linearalgorithm for this specific situation. We show, exploiting the concept of anoracle, that this approach is not of help to develop a faster generic algorithmfor deciding bisimilarity. For parallel algorithms there is a similar situationwhere these techniques may be applied, too
ミロのヴィーナスは日本のものか
No full textThe Venus of Milo is seen as a unique masterpiece of Greek art. However, to the great displeasure of the Greek authorities who are demanding its return, it has belonged to the French public collections since 1821. More generally, it is widely considered a European and Western heritage. And it goes without saying, its beauty is universal. But can it be Japanese? Through the examination of the reception of the Venus de Milo in Japan, the aim is to reflect on the conditions of a utopian appropriation of art works, given that, unlike texts that can be quoted, cut and mounted, paintings and statues are strongly dependant on their materiality. Against the current discourse on the dematerialization of art works, which goes hand in hand with an increasing fetishization of the originals, this article explores the path of an incorporation through practice and repetition.La Vénus de Milo est considérée comme un chef d’œuvre de l’art grec. Toutefois, au grand dam des autorités helléniques qui en demandent la restitution, elle appartient depuis 1821 aux collections publiques françaises. Plus généralement, on admettra volontiers qu’elle est européenne et occidentale. Et cela va sans dire, sa beauté est universelle. Mais peut-elle être japonaise ? À travers l’examen de la réception de la Vénus de Milo au Japon, il s’agira de réfléchir aux conditions d’une appropriation utopique des œuvres d’art plastiques, étant entendu que, contrairement aux textes qui peuvent être cités, tronqués, réédités, tableaux et statues sont puissamment assujettis à leur matérialité. À rebours des discours actuels sur la dématérialisation des œuvres, qui va de pair avec une fétichisation croissante des originaux, cet article explore le chemin d’une incorporation par l’usage et le refaire.ミロのヴィーナスは、ギリシャ美術の最高傑作と言われている。しかし、返還を求めるギリシャ政府の大いなる不興を買ったにもかかわらず、1821年以来、フランスの公的コレクションに所蔵されている。より一般的には、それがヨーロッパ的、西洋的であることは容易に認められよう。そして、言うまでもないが、その美しさは普遍的だ。ところで、ミロのヴィーナスは日本的なものといえるだろうか。引用やカットが可能なテキストとは異なり、絵画や彫像はその物質性に強く支配されていることから、日本におけるミロのヴィーナスの受容を通じて、芸術作品の自由な流用の条件について考察する。芸術作品の脱物質化をめぐる言説は、オリジナルのフェティッシュ化とともに進んでいるが、本稿では、実践と再制作による取り込みの道筋を探る