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On some 2-binomial coefficients of binary words: geometrical interpretation, partitions of integers, and fair words
No full textInternational audienceThe binomial notation (w u) represents the number of occurrences of the word u as a (scattered) subword in w. We first introduce and study possible uses of a geometrical interpretation of (w ab) and (w ba) when a and b are distinct letters. We then study the structure of the 2-binomial equivalence class of a binary word w (two words are 2-binomially equivalent if they have the same binomial coefficients, that is, the same numbers of occurrences, for each word of length at most 2). Especially we prove the existence of an isomorphism between the graph of the 2-binomial equivalence class of w with respect to a particular rewriting rule and the lattice of partitions of the integer (w ab) with (w a) parts and greatest part bounded by (w b). Finally we study binary fair words, the words over {a, b} having the same numbers of occurrences of ab and ba as subwords ((w ab) = (w ba)). In particular, we prove a recent conjecture related to a special case of the least square approximation
LLM-Assisted Relational Concept Analysis for Class Model Restructuring
No full textInternational audienceFormal Concept Analysis (FCA) and Relational Concept Analysis (RCA) have been used to assist software engineers restructure class models, with the aim of factoring common elements (e.g., attributes, methods) and revealing new abstractions, e.g., superclasses. Their foundations, based on lattice theory, lack "common-sense" knowledge to assess whether derived concepts correspond to relevant abstractions and, if so, to name them appropriately. This paper presents a methodology that combines FCA/RCA with Large Language Models (LLMs) to provide such assistance. Our approach builds on the existing literature by taking advantage of LLMs to address the naming problem of an entity (e.g. a class) and assess its relevancy. The results of several LLMs are compared and are encouraging
Adapting BERT and AgriBERT for agroecology: A small-corpus pretraining approach
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/614086/) * Autres projets (id;sigle;titre): 101081973;IntercropValuES;(EU) Developing Intercropping for agrifood Value chains and Ecosystem Services delivery in Europe and Southern countries//International audienceSource variables, or observable properties, used to describe agroecological experiments are often heterogeneous, non-standardized, and multilingual, making them challenging to understand, explain, and utilize in cropping system modeling and multicriteria evaluations of agroecological system performance. A potential solution is data annotation via a controlled vocabulary, known as candidate variables, from the Agroecological Global Information System (AEGIS). However, matching source and candidate variables via their textual descriptions remains a challenging task in agroecology. Domain-general language models, such as BERT, often struggle with domain-specific tasks due to their general-purpose training data. In the literature, these models are adapted to specialized domains through further pretraining, pretraining from scratch, and/or fine-tuning on downstream tasks. However, pretraining a domain-general model on a domain-specific corpus is resource-intensive, requiring substantial time, energy, and computational resources. To the best of our knowledge, no study has further pretrained a domain-general model on a small corpus (less than 100 MB) to adapt it to a domain-specific task and evaluated it on downstream tasks without fine-tuning. To address these shortcomings, this paper proposes further pretraining BERT and AgriBERT on a small agroecology-related corpus. This approach is designed to be both time- and resource-efficient while enhancing domain adaptation. We evaluate the pretrained models on the task of matching source and candidate variable descriptions without fine-tuning. Our results show that our further pretrained AgriBERT (+ Experts + Core) model outperforms all others by more than 8% from P@1 to P@10. These findings showed that small-scale pretraining can significantly improve performance on domain-specific tasks without requiring fine-tuning
Computation of the canonical tree decomposition of a rank-3 uniform oriented matroid into mutually avoiding parts
No full textIn [M. Bouvel, V. Féray, X. Goaoc and F. Koechlin. A canonical tree decomposition for chirotopes. Proceedings SoCG 2024] and [M. Bouvel, V. Féray, X. Goaoc and F. Koechlin. A canonical tree decomposition for order types, and some applications. SIAM J. Disc. Math., to appear - arXiv:2403.10311, 2024], the authors introduced a specific tree decomposition of a rank-3 acyclic uniform oriented matroid (or, in particular, of a finite set of points in general position on a plane) into mutually avoiding parts, by means of a geometric inductive construction. They raised the question of how to efficiently compute this tree decomposition. In this paper, we reformulate this decomposition in terms of the theory of tree representations of set families, especially of symmetric-crossing families. Using an appropriate data structure, we then answer the above question and give a method to compute this tree decomposition in time O(n^3) where n is the number of elements
De nouvelles architectures pour les Big Data
No full textEAN : 9782271153739International audienceContrairement aux systèmes SQL, conçus pour gérer des données structurées, les environnements big data reposent sur une architecture logicielle organisée en trois couches indépendantes : le stockage, la gestion des données et l'analyse. Cette sépara/on des couches a favorisé l'émergence d'un écosystème riche en ou/ls, frameworks et systèmes interopérables, fondés sur des architectures distribuées et parallèles. Dans ce chapitre, nous reviendrons sur la définition du big data ainsi que sur la gestion distribuée et parallèle des données, afin de présenter ces nouvelles architectures et leur intégration dans un environnement cloud
Section 06 Sciences de l’information : fondements de l’informatique, calculs, algorithmes, représentations, exploitations: Rapport de conjoncture 2024
No full textLa section 6 du Comité national de la recherche scientifique est, avec la section 7, une des deux sections traitant de la science informatique, et plus précisément de l’algorithmique et de la combinatoire, du calcul, du logiciel, de la sécurité, des réseaux et systèmes distribuées, des données et connaissances, de l’intelligence artificielle et de l’aide à la décision, ainsi que de la bio-informatique et de l’informatique quantique. Ce rapport présente le périmètre thématique de la section, discute de la place des femmes ainsi que des évolutions récentes des pratiques de recherche, présente la conjoncture des différents thèmes de recherche et enfin décrit les carrières au CNRS des chercheurs et chercheuses de la section
European Test Symposium Teams : an Anniversary Snapshot
No full textInternational audienceThe IEEE European Test Symposium (ETS) has been facilitating progress in electronic systems testing since its launch in 1996. On the occasion of its 30th anniversary, this collaborative paper gathers sections by 21 ETS teams to outline their influential ideas and milestones. Each team’s section highlights historical perspective, current research, frameworks and projects as well as forward-looking research agendas in the area of electronic-based circuits and systems testing, reliability, safety, security and validation. This anniversary summary documents how research of various ETS teams, exemplifying the test community, has been evolving and transitioning from concepts to practical standards and Electronic Design Automation (EDA) tools and flows. This legacy is a strong base to drive the next generation of advances in electronic systems testing
A platform for the mechanical and electrical characterization of 3D tissue engineered skeletal muscles
No full textInternational audienceIn vitro 3D skeletal muscle models attached to flexible pillars are particularly interesting to mimic in vivo muscle anchorage to the bone as well as analysing contraction. However, most systems provide limited (e.g. only mechanical) or destructive (e.g. histology) characterization. There is a need for sensors allowing continuous measurements to investigate transient responses and dynamics of tissue properties. In this context, bioimpedance measurement appears as a promising tool for achieving a more comprehensive characterization of muscle function and structure. We present here a platform designed to conduct both mechanical and electrical characterizations of a 3D in vitro model.PDMS chips with two pillars were designed using CAD software, a 3D printer and several molding steps [1]. Muscle tissues were generated by mixing C2C12 cells with a hydrogel [2]. To induce muscle contraction, we designed an electrical stimulation system comprising carbon electrodes, a waveform generator and ad hoc electronics [3]. The contraction force was assessed by measuring the bending of the pillars, through video analysis. In order to develop the bioimpedance measurement system, we first carried out Finite Element Method simulations (FEM) to optimize the sensitivity and compute the electrodes form factor. Electrodes were then fabricated using flexible printed circuit board technology. A custom hardware interface was designed to enable 4-point bioimpedance measurements with a commercial impedance analyzer.We first validated the culture protocol and the electrical stimulation system. After differentiation, we obtained mature and contractile 3D muscle tissues. Low frequency stimuli (1 Hz) induced twitch contractions while above 10 Hz we observed tetanic contractions. The bioimpedance system was characterized with Phosphate Buffered Saline, and the results were in agreement with our FEM simulations. Experiments are ongoing to validate our platform's ability to assess the bioimpedance of 3D muscle tissue
Disambiguation of Implicit Scientific References on X
No full textInternational audienceScientific discourse on the social web has been shown to compromise the accuracy of scientific findings. Complex scientific claims are uttered in the form of short snippets with "implicit references" (seen as references to scientific publications where the URLs to the actual studies are never cited). This has led to uninformed online scientific debates on topics such as health pandemics or climate. To enhance social media content, we introduce in this paper the novel task of disambiguation of implicit scientific references, where the goal is to retrieve the original scientific publications implicitly referred to by social media users. We contribute the first formalization, ground-truth corpus, and baselines for the task. With this work, we aim at shaping an understanding of implicit references on social media, and at laying a foundation for developing and evaluating methods for the disambiguation of implicit references
Task-blind adaptive virtual reality: Is it possible to help users without knowing their assignments?
No full textInternational audienceThe exploration of complex environments (reconstructed locations, immersive data visualisation, etc.) is one of the primary applications of virtual reality (VR) because of the feeling of immersion and the natural interactions that it provides. When exploration is completely free, users easily become disoriented and frustrated due to multiple factors such as task difficulty, interaction techniques, spatial understanding, immersion breaches, etc. Adaptive VR systems aim to overcome these difficulties and increase performance by providing clues to help the user and delivering effective feedback. Current adaptive VR systems are mainly task-based, meaning that they have explicit knowledge about what users must achieve. We assess a new task-blind approach, which aims to enhance users’ attention and recall processes instead of helping directly with their assignment by trying to infer in real time the task a user is performing. We compare three VR help-system configurations (task-based, task-blind, and no-help) through a controlled user study involving 66 participants. The results show that the group assisted by our task-blind system developed a different behavioural pattern while maintaining similar performance scores in comparison to the task-based approach. This paper shows a new way to offer more flexibility in help-system design and opens up the field of task-blind adaptive VR